Structural
Google Updates

April 2023 Reviews Update - 12/04/2023

Google released the new April 2023 reviews update on the 12th of April 2023. This is an update building on the original 6 product review updates that had been released previously. This will go beyond product reviews and will look to evaluate all types of reviews with topics focusing on areas related to services and businesses, products, destinations, and media (games, movies, tv shows etc.). 

This update will impact the following languages: English, Spanish, German, French, Italian, Vietnamese, Indonesian, Russian, Dutch, Portuguese and Polish. 

Google shared 14 best practices for what it will consider high-quality reviews:

• Evaluate from a user’s perspective.
• Demonstrate that you are an expert or knowledgeable about the review topic.
• Provide images, video, audio, or other material from your personal experience to support your review.
• Share (if available) quantitative measurements when assessing performance.
• Explain how the subject item/topic sets itself apart from its competitors.
• Cover any comparable pieces and go through which might be best in various use cases. 
• Thoroughly discuss the pros and cons. 
• Describe any changes that have been made since a previous model/iteration and why the user might benefit from the latest model. 
• Focus on the most important decision-making factors
• Describe how a product has been designed and the effect this will have for users (beyond what has been stated by the manufacturer).
• Include links to other useful resources to help users make a decision.
• Consider linking to multiple sellers to give users more choices.
• When recommending something as the best choice, use first-hand information as to why you consider this the best. 
• Ensure there is enough useful content in your ranked lists for them to stand on their own, even if you choose to write separate in-depth single reviews.

+SELand

March 2023 Core Algorithm Update - 15/03/2023

Google Search Central released the March 2023 core update on the 15th of March 2023, the first core update of 2023. This will take roughly two weeks to roll out. 

As usual, this update aims to prioritise the rankings of pages that provide the most value on Google's search results, therefore there may be some shuffling of results over the next few weeks. 

+GoogleSearchCentral

+SELand

February 2023 Product Reviews Update - 21/02/2023

The sixth iteration of the product reviews update has been released on the 21st of February 2023. Named the February 2023 product reviews update, Google has said this will take about two weeks to roll out. Google Search Central has also stated that this update will now also apply to the following global languages; Spanish, German, French, Italian, Vietnamese, Indonesian, Russian, Dutch, Portuguese, and Polish (as well as English). 

Each one of these updates seeks to provide Google Search users with higher-quality results regarding those related product reviews. To benefit from these updates, websites should aim to regularly update any content related to products and make sure these are as descriptive and useful to users as possible. 

+SELand

December 2022 Spam Update - 14/12/2022

Google has rolled out the December 2022 link spam update which will take two weeks to roll out. This update is global and aims to leverage SpamBrain which was referenced back in 2018. 

SpamBrain aims to remove or punish spam sites as much as possible. Google states that the site algorithm learns by comparing your website to other 'spammy' websites. The more high-quality the content is on your website, the less likely that it will be detected as spam, so this means sites should aim to keep clear of manipulative keywords, cloaking techniques or hidden text as these have been perceived as techniques used by spam websites. 

+SELand

December 2022 Google Helpful Content Update - 05/12/2022

On the 5th of December 2022, another helpful content update started rolling out. This aimed to improve on the original update that was announced back in August. 

Google wants to reward pages that provide useful information and have been created with people in mind rather than those created with the intention to rank well. 

For those wanting to rank well, you will need to make sure that you update your long-form content in line with Google's recommendations. 

+SEJournal

October 2022 Spam Update - 19/10/2022

Google released the first spam update of 2022 on the 19th of October 2022, the last one being reported in November 2021. This took less than 48 hours to fully roll out and the update is a global one, affecting all languages not just English language sites. 

+SELand

+SERoundtable

September 2022 Core Algorithm Update - 12/09/2022

Google announced that they had started the September core algorithm update on the 12th of September 2022. This rollout should take around 2 weeks to finish. 

This is the second core update of the year with the last being reported in May 2022. 

+SELand

Google Helpful Content Update - 25/08/2022

Google started rolling out a new update called the Helpful Content Update on the 25th of August 2022. This was completed 15 days on September 9th. 

This update intends to target websites with a large amount of unhelpful content. This is content that has been primarily created to rank on search engines rather than satisfactorily informing human readers. 

This is a site-wide algorithm update that intends to downgrade any sites that have a high amount of SEO content while promoting more helpful content. It is not like other algorithm updates which will be applied on a page-by-page basis. While the update is not niche-specific, Google mentioned that the content that will be impacted most will be: online educational materials, arts and entertainment, shopping and tech-related content as these spaces have traditionally had a high proportion of SEO content. 

This will initially launch for English language searches globally but may expand to other languages in the future. 

+SELand

+SEJournal

August 2022 Service Outage - 08/08/2022

On 8th August 2022, Google Search, Maps and Drive went down with many users around the world reporting a brief outage. This caused some disruption in rankings and indexing for a brief period of time. According to Google, this was due to a software update. 

+SEJournal

July 2022 Product Reviews Update - 27/07/2022

Google released the fourth product review update which started rolling out on the 27th of July 2022. This aims to reduce the visibility of low-quality reviews and show higher-quality reviews. 

+SEJournal

May 2022 Core Update - 25/05/2022

Google announced that the May 2022 core update had been released on the 25th of May 2022. As usual, this should take about 1-2 weeks to roll out and some changes may be noticed in search performance during this period. 

This is the first core update of 2022 since the last one that rolled out in November 2021. Google has recommended improving and updating your content to its best possible version should you notice any reduction in ranking performance. 

+ Google Developers

March 2022 Product Reviews Update - 23/03/2022

Google has started rolling out the third products reviews update. This algorithm update targets product review-related content that is ranking on the web or more specifically, Google's search results. It aims to promote the most useful and helpful content to searchers. Thus, any content that is deemed similar to template-like information found on the web will not benefit from this series of updates.  

Google has stated the following will matter with the product reviews update:

• Include in-depth detail such as the pros and cons of a product, how it performs day to day, and other useful information such as if there are any major/minor differences between the latest model and older iterations/generations. 
• The content has been provided by those who have used the products themselves, detailing how it can be used and what it physically is like 
• Include unique information (e.g. visual, audio or linked to other content that demonstrates reviewer's experience of the product) beyond what has been given by the manufacturer or any other official sources. 
• Coverage of similar or comparable products, or adequate explanation of what makes the product stand out from its competitors

This update will roll out for the next few weeks. The majority of ranking volatility will most likely occur in the early stages of the rollout. For now, these updates will affect English-language product reviews. However, Google is planning to open up product review support for more languages in the future, so the update may impact non-English product reviews when this happens. 

+SELand

Google Desktop Page Experience Update - 22/02/2022

The Google Desktop Page Experience update started rolling out on February 22nd. This update is meant to build on top of the page experience update that was rolled out on mobile from June and August 2021. This rollout completed on March 3rd 2022. 

December 2021 Product Reviews Update - 01/12/2021

Google started the second product reviews update called the December 2021 products reviews update on the 1st of December 2021. 

The intention of this update is to reward product reviews that provide in-depth information and demonstrate research has been put in rather than thin content or content that are effectively just summaries of products. Insightful analysis and original research are intended to be the winners of the product reviews update. 

Google has stated that if you made changes between the latest update (December 2021) and the previous update (April 2021), you may see improvements to your rankings as this update rolls out. 

Google provided two pieces of advice around this update:

• Provide evidence (e.g. visual, audio, links of your experience with the product) to support your narrative and demonstrate the authenticity of your product review.
• Include links to multiple sellers, which will provide users with enough choice when deciding to purchase.

Google has stated that the update will take three weeks to complete and is rolling only for English-language pages. 

+SELand 

November 2021 Local Search Update - 30/11/2021

Google confirmed that had run a local search ranking update between November 30th and December 8th. According to Google, the update was to rebalance factors that they consider when generating local search results. During this period there may have significant local ranking changes in Google Maps and local pack results.

+SELand

November 2021 Core Update - 17/11/2021

Google announced the rollout of their latest broad core algorithmn update on November 17th 2021. Google has stated that the update would typically take 1-2 weeks to roll out. This core update was reportedly more volatile than the July 2021 update. It was reported that desktop search results saw 12% more volatility, while the mobile results saw 23% more volatility. 

+SELand

November 2021 Spam Update - 03/11/2021

Google announced that it was rolling out a November 2021 Spam update on the 3rd of November. This is likely to complete over a period of a week. Google has not specifically stated whether this will be specifically targetting link spam, content spam, or any other type of search-related spam. 

It's possible that this is a broad spam update, as Google has only said that it will target content that goes against Google's webmaster guidelines. 

+SERoundtable

June 2021 Spam Update (Second Part) - 28/07/2021

The second part of the June 2021 spam update started rolling out. This is a general spam update and does not target anything specifically. 

+Google

Google July 2021 Core Update - 01/07/2021

From the first to the 12th of July 2021, the second part of the core algorithms that were announced rolled out (the July 2021 core algorithm update). 

Some data so far, suggests the July update was smaller and less impactful than the June core update, however, the vast majority of any changes seen in your rankings would have occurred from the 2nd to the 9th of July. 

+SELand

June 2021 Spam Update - 23/06/2021

Google confirmed that a search 'spam update' started rolling out on the 23rd of June 2021. The update started and was completed that day. 

+Google

Google Page Experience Update - 15/06/2021

Google announced that it was slowly rolling out the page experience update on the 15th of June 2021. Which will continue to roll out until the end of August 2021. Google also mentioned that Top Stores will also stop using AMP and will use this new signal by the 17th of June 2021. 

As this rollout will be slow, there should not be drastic changes. The update is mainly focused on highlighting pages that offer great user experiences, so for most sites, massive changes should not be seen. 

By end of August, all the core web vital metrics such as LCP, FID, and CLS should have been included in the update. 

+SELand

Google June 2021 Core Update - 02/06/2021

On the 2nd of June 2021, the first in a pair of core algorithm updates started rolling out. The first is the June 2021 core update, with the second, July 2021 core update, following in the next month. 

As Google are not fully ready to release all their planned improvements, they have decided to move ahead with the elements which are ready, hence why we are seeing two updates being pushed out. 

There is no information as to what is being changed or updated, however, any changes that occur with the first instance of the core algorithm update may alter with the rollout of the second update. 

+SELand

Google Products Review Update - 08/04/2021

Google launched a new ranking algorithm update that aims to promote higher quality product review content called the 'Google product reviews' update.

This is not a core update, and there are no penalties associated with this update but Google intends to promote product review content that provides unique and insightful analyses. 

This update will only affect English language results for the current time.  

+SELand

Google Passage Ranking - 10/02/2021

Passage ranking went live on the 10th of February 2021, for English queries in the US. This is a new way for Google to rank specific passages from a web page in search.

What this means is that they will not just index web pages, but individual passages from the pages that it has crawled. Google has said that this new ranking update will affect 7% of search queries across all languages when fully rolled out globally.

+SELand

Broad Core Algorithm Update - 03/12/2020

Google announced that it was rolling out the third core algorithm update of the calendar year on the 3rd of December 2020. 

Within the first 24 hours of the rollout, some sites were reporting wins and losses over 30%.

+SEJournal

Google “Subtopics” Update - 16/11/2020

Google launched the 'subtopics' update to the algorithm in mid-November 2020. Google wants to "understand subtopics around an interest, which helps deliver a greater diversity of content when you search for something broad.". The idea is that Google wants to show more diverse updates on search results for broad or vague searches. 

This has the potential to make certain keywords more competitive. Pages that have not appeared on the first page may start appearing if they offer a great detail of information in certain aspects of a subject. 

+SERoundtable

Google Indexing Glitch - 10/08/2020

On August 10th and 11th, Google reported that they had an indexing glitch which impacted search results around this time. 

This glitch appeared to affect all languages, countries and niches, however, it was Ecommerce sites that reported the most extreme fluctuation in rankings. 

The cause of the glitch was related to Google's indexing system

+ SEJournal

Google July 2021 Core Update - 01/07/2020

Google has announced that the second part of the core algorithm began rolling out on the 1st of July. This should take 1-2 weeks to roll out fully. 

More information to follow on what impact this update may have.

+SELand

Broad Core Algorithm Update - 04/05/2020

Google announced that they were rolling out a core update commencing on the 4th of May 2020. The May 2020 Core Update is expected to roll out over one or two weeks. Keep watch on your search results to see what impact this will have on your website. 

+SERoundtable

Featured Snippet Update - 22/01/2020

Google has confirmed that if a web page listing is in the featured snippet position, it's listing is no longer repeated in the search results. The reasoning behind this is to declutter the results, thus the featured snippets now count as one of the ten web page listings. This rolled out fully on the 22nd of January 2020. 

+SERoundtable

Broad Core Algorithm Update - 13/01/2020

Google pre-announced a core update rolling out on the 13th of January 2020. The January 2020 Core Update is live and will continue to roll out over the next few days. 

Further insight will follow in an update. 

+Google

+Search Engine Land

Google BERT Update - 23/10/2019

Google have announced what they called the most important update in five years. 

Google released the BERT algorithm update, which attempts to understand queries the way that humans understand them. The BERT update impacts 10% of search queries.This update is similar in nature to RankBrain. This is a deep learning algorithm related to natural language processing, it helps Google to understand what words in a sentence mean. Effectively, this is about understanding more longer tail, more natural language queries. 

+SEJournal

Broad Core Algorithm Update - 24/09/2019

Google announced they were rolling out the September core algorithm update on the 24th of September. Unlike previous updates, this update took a little longer than usual to be fully completed. This update appeared to have a large effect on ranking for YMYL (Your Money or Your Life) sites. However, it has been argued that the impact on these sites was much larger during the June update.

+ SERoundtable

+ Google

Google Maverick - 18/07/2019

Nicknamed the 'Google Maverick', this update was picked up after fluctuations were reported starting around July 11th.

Google search results fluctuations finally peaked on July 18th. While this has not been officially reported as an update by Google. The level of activity that has been picked up maybe some indication of a quick update. 

+Search Engine Roundtable

Diversity Update - 06/06/2019

Separate to the core algorithm update, Google announced that they had rolled out an update to provide more site diversity in their results. 

Google is looking to not show more than two results from the same domain with this search update. But may show more than two results from the same domain name where appropriate. 

+Search Engine Land 

Broad Core Algorithm Update - 03/06/2019

Google announced that a broad core algorithm update took place on the 3rd of June 2019. 

Some UK News publishers reported a heavy impact to their search traffic. It was reported that sites affected by previous core updates had not been affected by this update. 

+Search Engine Journal

Broad Core Algorithm Update - 12/03/2019

On the 12th of March Google confirmed a core search algorithm update.

It is a little early to find out what has changed. Further insight will follow in an update. 

+Search Engine Land

Unnamed Update - 07/02/2019

SERP Volatility looking very high today. Clear signs of a Google search ranking algorithm update. There have been reports of position changes across numerous sites, including chatter in the forums. Most of the signs appear to be prominent within the UK.

+Search Engine Roundtable

Unnamed Update - 05/01/2019

Some forum chatter on a possible larger Google Search algorithm update of 2019. This may have started during the weekend around the 5th or 6th of January and seems to have continued until January 7th. So far, there have been indications to suggest that this update may be favouring long tail key terms with some reports of improved traffic and ranking positions.

Further information followed over the course of the next few days with reports of noticeable changes reported in the SERPs. There has been conversation surrounding a big hit around January 9th. Not confirmed by Google. 

+Search Engine Roundtable

+Search Engine Roundtable

Unconfirmed Update - 14/12/2018

A pre-christmas Algo Update? Possibly. Chatter is limited on the forums, but there are some users reporting big swings in traffic over the last few days. So we are calling this one and adding it to the Panguin Algo timeline. From what we've read, this update seems to be favouring established brands.

Halloween Update - 25/10/2018

Some forum chatter going on about a possible update, plus several of the SERP tracking tools have picked-up above normal flux. Not confirmed by Google. Could possibly be targeted at specific niches.
+Search Engine Roundtable
+Search Engine Roundtable - further update 6th Nov

Unnamed Update - 16/10/2018

Some forum chatter going on about a possible update, plus several of the SERP tracking tools have picked-up above normal flux. Not confirmed by Google.
+Search Engine Roundtable

Unnamed Update - 08/10/2018

Some forum chatter going on about a possible update, plus several of the SERP tracking tools have picked-up above normal flux. Not confirmed by Google.
+Search Engine Roundtable

Unnamed Update - 04/10/2018

Possibly a tweak to the Google Birthday Update (27th Sept), but a bit of forum chatter going on about a possible update, plus several of the SERP tracking tools have picked-up above normal flux. Not confirmed by Google.
+Search Engine Roundtable

Google Birthday Update - 26/09/2018

Towards the end of the month Barry Schwartz was able to confirm with Danny Sullivan of Google that there had indeed been a more minor update that started impacting on the 26th September. However, the wording 'small' is in relation to the number of websites impacted, and not the level of impact (which has been big) for those hit by it.
+Search Engine Roundtable
+Search Engine Roundtable
+Rank Ranger - in-depth analysis

Google Images Update - 24/09/2018

Google announced that it's bringing its image search more in-line with its regular SERP ranking algorithm. In other words they'll now be using things like a website's overall authority to rank its images in image search (and therefore what you see in main SERP image features when they appear). Content freshness was also a factor that was cited as now having greater importance in image search.
+Search Engine Roundtable

Unnamed Update - 19/09/2018

A bit of forum chatter going on about a possible update, plus several of the SERP tracking tools have picked-up above normal flux. Could be an update. Not confirmed by Google
+Search Engine Roundtable

Unnamed Update - 11/09/2018

A bit of forum chatter going on about a possible update, plus several of the SERP tracking tools have picked-up above normal flux. Could be an update. Not confirmed by Google
+Search Engine Roundtable

Unnamed Update - 22/08/2018

A bit of forum chatter (not lots) going on about a possible update, plus several of the SERP tracking tools have picked-up above normal flux. Could be an update. Not confirmed by Google. May be a tweak to 1st August (Medic) update
+Search Engine Roundtable
+Search Engine Land - analysis by Eric Enge

Core Quality (Medic) Update - 01/08/2018

Google has confirmed it has rolled out another of its broad core quality algorithm updates. The roll-out finished around Wednesday 8th August. The advice from G hasn't changed, in that there's nothing specific to optimise or re-optimise for. If you've seen a dip coinciding with this update, and you haven't changed anything on your website, then it could be your competitors have done something new, or something they were already doing is now being given more credit.

ACTION: If the above is the case for you, then a thorough competitior analysis combined with a keyword/topic content gap analysis is often a great way forward. If you'd like some help with that, then drop us a line.

+Google Announcement
+Search Engine Roundtable
+Search Engine Land
+Search Engine Land - still rolling out
+Search Engine Land - fully rolled out
+Search Engine Roundtable - Not just health

Speed Update - 09/07/2018

After 6 months of build-up, Google has released its "Speed Update". This is an aknowledged and "named" Google update. Up to this point, website speed has been a ranking factor for desktop search, but not mobile search. This update brings website speed as a ranking factor to mobile search. As with the desktop version, this will only affect the slowest loading websites in terms of a ranking signal (and only for some queries). Essentially, if you're giving users a poor experience on mobile due to your website loading slowly, you can reasonably expect you mobile Google rankings to drop.

REMEMBER: toggle "Mobile" above your Panguin chart and click "Go", to only look at your Google organic mobile traffic.

ACTION: If you're worried about your website's speed and you'd like some help, then drop us a line. We can audit your website's speed, tell you what needs to be done and implement it for you (if you don't have internal dev resource).

+Google Announcement
+Search Engine Land Announcement
+Search Engine Land FAQs

Unnamed Update - 18/06/2018

A bit of forum chatter going on around ranking flux, plus several of the SERP tracking tools have picked-up above normal flux. Could be an update. Not confirmed by Google.
+Search Engine Roundtable

Video Carousels - 15/06/2018

Google has replaced the old-style video thumbnail results in the SERPs, with scroll-able (left and right) video carousels that seem to be displaying on average 8+ videos in a sequence. The change started on about the 6th June, but really hit home on the 15th June.
+Search Engine Land

Unnamed Update - 08/06/2018

A bit of forum chatter going on around ranking flux, plus several of the SERP tracking tools have picked-up above normal flux. Could be an update. Not confirmed by Google.
+Search Engine Roundtable

Unnamed Update - 24/05/2018

A bit of forum chatter going on around ranking flux, plus several of the SERP tracking tools have picked-up above normal flux. Could be an update. Not confirmed by Google.
+Search Engine Roundtable

Unnamed Update - 14/05/2018

A bit of forum chatter going on around ranking flux, plus several of the SERP tracking tools have picked-up above normal flux. Could be an update. Not confirmed by Google.
+Search Engine Roundtable

Core Quality Update - 16/04/2018

After a pretty crazy March in terms of volatility in the SERPs, April looks as though it's now heating up as well. This update has been confirmed by Google as another core update and continued rolling out (and causing flux) for well over a week (more like 2).
+Search Engine Roundtable
+Search Engine Roundtable
+Search Engine Roundtable

Core Quality Update (cont) - 28/03/2018

Another suspected continuation of major core quality update from earlier in the month. The original update has been confirmed by Google and was designed to help websites that have been under-rewarded. That means it is rewarding rather than penalising. If you've been 'hit,' then it's a case of improving quality of content and links (Expertise, Authority, Trust - EAT) and user experience quality. You've seen a hit because your competitors have improved.
+Search Engine Roundtable

Core Quality Update (cont) - 23/03/2018

Suspected continuation of major core quality update from earlier in the month. The original update has been confirmed by Google and was designed to help websites that have been under-rewarded. That means it is rewarding rather than penalising. If you've been 'hit,' then it's a case of improving quality of content and links (Expertise, Authority, Trust - EAT) and user experience quality. You've seen a hit because your competitors have improved.
+Search Engine Roundtable

Core Quality Update (Brackets Part 2) - 14/03/2018

Continuing on from the major core quality update from a week previous, more major SERP flux is being reported. This update has been confirmed by Google and has been designed to help websites that have been under-rewarded. That means it is rewarding rather than penalising. If you've been 'hit,' then it's a case of improving quality of content and links (Expertise, Authority, Trust - EAT) and user experience quality. You've seen a hit because your competitors have improved.
+G-Squared Interactive
+Search Engine Roundtable
+Search Engine Land

Answers Without Search Results - 13/03/2018

Google has rolled-out an experiment (viewable by everyone) whereby certain search queries are triggering an asnwer only, with no search results. Here's what Google's Danny Sullivan had to say in his tweet, "For calculator, unit converter & local time, we’re experimenting with a condensed view to further speed up load time. People who search for these tools rarely use full search results, but the results will remain available for those who want them via the 'Show all results' button."
+Search Engine Roundtable
+Search Engine Roundtable
+Search Engine Roundtable

Google Posts - for musicians - 08/03/2018

Google is expanding its "Google Posts" SERP feature to any musicians that have knowledge pannel results. This is the feature that allows verified entities and organisations the ability to post content direct to the Google servers and have it appear alongside their knowledge panels. Google Posts where originally trialled for Trump and Clinton during their presidential election race.
+Search Engine Land
+Google

Core Quality Update (Brackets Part 1) - 07/03/2018

Google has confirmed they have released one of their regular ("several times a year") core quality algorithm updates. Here is Google's statement on Twitter:
"Each day, Google usually releases one or more changes designed to improve our results. Some are focused around specific improvements. Some are broad changes. Last week, we released a broad core algorithm update. We do these routinely several times per year. As with any update, some sites may note drops or gains. There’s nothing wrong with pages that may now perform less well. Instead, it’s that changes to our systems are benefiting pages that were previously under-rewarded. There’s no “fix” for pages that may perform less well other than to remain focused on building great content. Over time, it may be that your content may rise relative to other pages."
+Search Engine Roundtable
+Search Engine Land
+G-Squared Interactive

Multiple Answer Boxes - 28/02/2018

Starting today, Google is rolling out multiple "answer boxes" for some search queries. Also known as "organic position zero," "answer boxes" are designed to answer a search query without clicking any further than Google's search results. However, they do include a link throught to the website that has profered the information that Google has scraped (thus the website in question whose content has been scraped by Google leap-frogs the queue to the top of the SERP). The kind of queries that will receive more answer boxes are:

• Queries/searches that already trigger an answer box
• Queries/searches where the question has a degree of ambiguity in terms of searcher intent

By way of showing the user that it is trying to both understand the intent and answer the query, Google will show multiple answer boxes and rewrite the question in each instance, so as to show the user which interpretation of their query is being answered.

Immediate implications are that more SERP real estate is going to be taken up and we now have Position Zero, Position Zero +1 and so on in Google organic search. This spells more opportunity in terms of optimising for answer cards, but also a threat for "conventional" organic SERP entriesRoll-out begins today on mobile and will propagate to desktop in time.

+Google Announcement
+Search Engine Land

Unnamed Update - 20/02/2018

After a relatively quiet start to February, we have a possible algorithm update kicking-in on or around the 20th - nothing crazy, but there's deffinitely been a bit of webmaster/seo chatter alluding to SERP flux.
+Search Engine Roundtable

Unnamed Update - 15/02/2018

After a "Happy New Year" from the algorithm on the 8th Jan, the theme looks to be continuing. More algorithm tweaks, again seemingly off the back of what was done in December. SERP flux and subsequent webmaster chatter ensued.
+Search Engine Roundtable

Unnamed Update - 08/01/2018

In what seems like a continuation of the December algorithm change bonanza, there has been a noticable up-tick in webmaster and SEO chatter reporting on flux in the Google SERPs. Barry Schwartz of Search Engine Roundtable postulated that this may have been tweaks to the preceeding December updates. That's unconfirmed, but certainly well within the realms of possibility.
+Search Engine Roundtable

Unnamed Update - unnatural links - 26/12/2017

Off the back of blackhat chatter and complaints, Google seems to have released an update that targets private blog networks (PBNs), link spam and other unnatural link acquisition. Too early to tell if just a mass set of manual penalties being issued, or something algorithmic (or both!).
+Search Engine Roundtable
+G-Squared Interactive - December Analysis

Celebrity Update - 15/12/2017

Google has released an update that seems to have had the effect of impacting celebrity websites. One possible reason for the consistent drop is that prior to the 15th, celebrity sites have been treated differently to other websites by Google's algorithm. The fact is, many celebrity websites are not good from an SEO/content best practice point of view. A case in point is that Katy Perry's site has stayed at the top of the SERPs for her 'brand' term and is markedly better from an SEO/content point of view than many others.
+G-Squared Interactive
+G-Squared Interactive - December Analysis

Maccabees Update(s) - 12/12/2017

Google has confirmed it's released several updates at around this time. These have been grouped (for now) under the title 'Maccabees' as the chages associated with this update are the most widespread.

The first major symptom seems to be that websites using doorway pages have been hit hard. In other words, websites with a large number of landing pages targeting large arrays of keyword permutations. If you're a business with a set of services that you deliver to different locations, and you have an array of very similar (to each other) pages on your website that target each service for each location, then Google (it would seem) has you in its cross-hairs.

Symptom two is more akin to Fred and the core quality updates that police low value and ad-heavy, or affiliate-heavy websites. All that aside, there does seem to be some collateral damage with this update, with good websites being unfairly hit. Possibly some algo tweaking required from Google here!

+Search Engine Roundtable
+Search Engine Roundtable - Analysis
+Search Engine Land
+G-Squared Interactive - December Analysis
+Google - what is a doorway page?
+Wikipedia - who were the Maccabees?

Unnamed Update - 05/12/2017

This update looked like a pre-cursor to what then happened on the 12th December - a group of quality focused updates under the title "Maccabee's Update." Essentially, it targeted websites with a high number of very similar (to each other) pages, created for the purposes of targeting many keyword permutations e.g. services + locations. In other words, "Doorway Pages." These pages tend to offer poor user experiences and are usually designed purely to capture organic traffic, to then have it convert elsewhere on the given website.
+G-Squared Interactive - December Analysis
+Google - what is a doorway page?
+Wikipedia - who were the Maccabees?

Mobile First Index - 07/10/2017

Gary Illyes a Google Webmaster Trends Analyst has recently announced that the first mobile-index is gradually being implemented, initially starting with just a 'few sites'. However, when looking at the number of sites indexed by Google, a 'few' could actually relate to a significant number of websites. Illyes replied that there was no reason to be concerned with the rollout because Google are still in the testing phase and the implementation will be carried out very slowly. Gary Illyes further added that a full rollout and implementation of the mobile-first index would not be in the foreseeable future. This admission certainly came as a surprise as the rollout was not expected until 2018. It appears however that encouraging initial results have encouraged Google to proceed with the index.
+Search Engine Land
+Search Engine Land - FAQs

Unnamed Update - 27/09/2017

It was on Tuesday that small changes began to appear in relation to the Google algorithm and rankings throughout the SEO industry and search results. Considerable discussion has taken place in SEO forums and algorithm monitoring tools have been responding to the latest round of changes, some of which have been significant. The combination of SEO discussion and movement in rankings has continued through to the 29th. Webmasters and SEOs remain alert as the changes continue to take place. 
+Search Engine Roundtable
+Search Engine Roundtable

Unnamed Update - 19/09/2017

It was over the weekend of the 16th that concern was raised over Google search results, particularly within the ongoing thread in WebmasterWorld and in discussions in Black Hat World. A flurry of comments began on Saturday but the discussion quickly faded. It is thought that whatever occurred on Saturday was quickly remedied on Sunday. Then, the following Tuesday (the 19th) movement began again with another flux in the search engine results. 
+Search Engine Roundtable 16th
+Search Engine Roundtable 19th

Unnamed Update - 16/09/2017

On the weekend of the 16th, there were many people expressing concern over the Google search results particularly in the WebmasterWorld thread and Black Hat World. Initial concern was expressed early on Saturday, but the discussions quickly faded. It was thought that whatever changes that were made on Saturday morning were addressed the following day. On Tuesday the 19th further chatter and SERP flux were reported which may have indicated some further changes.
+Search Engine Roundtable 16th
+Search Engine Roundtable 19th

Unnamed Update - 08/09/2017

A heightened level of chatter from Webmasters highlighted that a potential algorithm update was to take place on 6th September and there followed a sustained period of discussion surrounding an update to the SERPs on Google. It is however unclear whether the two of these occurrences are related in terms of an update.
+Search Engine Roundtable 6th
+Search Engine Roundtable 8th

Possum 2 - 22/08/2017

Joy Hawkins, a local search expert identified that a local pack algorithm update which occurred a year ago, nicknamed the Possum update has significantly decreased in activity since 22 August 2017.
+Sterling Sky
+Search Engine Roundtable

Unnamed Update - 19/08/2017

It appears that Google have been pushing quality updates on a monthly basis now (undertaking a refresh of its algorithms in relation to quality) and this is just another of those updates.
+Search Engine Roundtable
+G-Squared Interactive

Unnamed Update - 25/06/2017

It appeared that around Sunday, June 25, Google began to roll out a large search algorithm update. Although the updates were not confirmed beyond the standard reply from John Mueller, increased discussion in the industry indicated that a real Google algorithm update had taken place.
+Search Engine Roundtable
+Search Engine Roundtable
+Rank Ranger

Google Posts - for all GMB users - 22/06/2017

Google is expanding its "Google Posts" SERP feature to all Google My Business users. This is the feature that allows verified entities and organisations the ability to post content direct to the Google servers and have it appear alongside their knowledge panels. Google Posts where originally trialled for Trump and Clinton during their presidential election race.
+Search Engine Land
+Google

Local Panel Update - 07/06/2017

Following a month of testing, confirmation came from Google with Search Engine Land that a new user experience had been fully implemented for both local panel and mobile search results. Consequently, users can now quickly toggle between the overview information for local business and their corresponding customer review tab.
+Search Engine Land
+Search Engine Roundtable

Unnamed Update - 17/05/2017

It was noted today that some SEOs and webmasters began to notice that automated tracking tools were picking up on signs that would point to a large Google algorithm update. That being said, there hasn't been a huge number of webmasters or SEOs raising concern in white hat or black hat forums.
+Search Engine Roundtable
+Search Engine Roundtable
+Search Engine Roundtable
+G-Squared Interactive

Unnamed Update - 04/05/2017

Glenn Gabe over at G-Squared Interactive commented that since the Autumn of 2016, a series of updates were carried out in a very short timeframe. He had hinted that Google may be increasing the frequency of their 'quality updates'. In his eyes, 2017 has certainly followed that pattern. He further states that early indications show core ranking updates that focus on quality have been increasing in frequency. He lists the updates relevant to this that have happened since the beginning of 2017, as follows:

• 5 January 2017
• 7 February 2017
• 7 March 2017 (Fred)
• 26 April 2017
• 4 May 2017
• 17 May 2017

As can be seen, the updates have changed from every few months to monthly or (on some occasions) even more frequently.

Local 'Superlative' Update (US Only) - 27/04/2017

It is important for local businesses to receive good reviews and positive ratings and this seems to be increasingly relevant. It was only yesterday that Google began to include the quality element into the snack pack interface in relation to some local searches, particularly when key search terms such as 'best' and 'great' were used (applicable to the US only).
+Search Engine Land

Unnamed Update - 26/04/2017

Glenn Gabe over at G-Squared Interactive commented that since the Autumn of 2016, a series of updates were carried out in a very short timeframe. He had hinted that Google may be increasing the frequency of their 'quality updates'. In his eyes, 2017 has certainly followed that pattern. He further states that early indications show core ranking updates that focus on quality have been increasing in frequency. He lists the updates relevant to this that have happened since the beginning of 2017, as follows:

• 5 January 2017
• 7 February 2017
• 7 March 2017 (Fred)
• 26 April 2017
• 4 May 2017
• 17 May 2017

As you can see, the updates appear to have changed. Previously they were carried out every few months. Recently they have switched from every few months to monthly or even more often than this.

Project Owl - 25/04/2017

Project Owl created by Google was a three pronged attack focusing on problematic content and fake news.  'Project Owl' Google aimed to improve results by focusing on authoritative content and obtaining feedback regarding Featured Snippets answers and suggested searches. Google are aware that they have a search quality problem. It has been plagued since November with concerns about offensive search suggestions, unsettling answers and fake news which have been appearing at the top of the SERPs. Project Owl was created in an attempt to address these important issues. Google have stated however that this issue affects 0.25% of all search queries. The algorithmic search quality changes are approximately 10% implemented and are likely to reach 100% in the following days. However, despite these changes, Google are aware that they cannot eliminate the problem entirely.

+Search Engine Land
+Search Engine Roundtable
+The Telegraph

Unnamed Update - 17/04/2017

It appears that there has been some form of update. Although the update doesn't appear to be at the same levels of Penguin, Panda or Fred, a significant update has caused a lot of discussion in the community and has been picked up by automated tracking tools.
+Search Engine Roundtable

Google Posts - 22/03/2017

Google are allowing more verified entities and organisations the ability to post content direct to the Google servers and have it appear alongside their knowledge panels (sometimes above, sometimes below). Google Posts where originally trialled for Trump and Clinton during their presidential election race, but has now been extended for museums, movies, musicians & sports groups.
+Search Engine Land
+Google

Unnamed Update (content related) - 07/03/2017

This latest update appears to be unrelated to the unconfirmed link algorithm change that occurred earlier in February. It seems that this latest update is more related to Panda because it is based around issues such as site quality and content as opposed to link factors.
+Search Engine Roundtable
+Search Engine Roundtable
+Search Engine Land

Fred Update - 07/03/2017

It has been acknowledged, albeit reluctantly that the Fred Update was launched at the beginning of March 2017. Fred has caused quite a bit of trepidation within the SEO community because some webmasters have witnessed a substantial drop in traffic. For some as much as 90%. 

Key Points on the Google Fred Penalty:

• It seems that Fred is a core Google algorithm update
• In the majority of cases, the update hit affiliate websites with thin content and those without a clearly defined content theme
• Websites with poor backlinks were also hit
• A number of sites felt the impact of the Fred update. To facilitate the recovery process it is important to identify the key areas that were penalised and focus on improving them
• Improvements to recover from the penalty will include removing, updating or redirecting poor content, reducing ads and reviewing backlink profiles to improve clarity

The name of the update "Fred" was created by Gary Illyes from Google who jokingly mentioned that all Google updates should be called "Fred."

+Ignite Visibility - Fred Analysis
+Search Engine Land - Google confirms update
+Search Engine Land
+Search Engine Roundtable
+maavdnbo.be
+Search Engine Roundtable

Unnamed Major Update - 07/02/2017

While this update doesn't seem to relate to anything specific such as links or spam, it seems to be related to a normal, yet unconfirmed Google update which results in changes to rankings in the SERPs.
+Search Engine Roundtable
+Search Engine Roundtable
+G-Squared Interactive

Japanese Content Quality Update - 03/02/2017

This morning, a significant algorithm update hit Google Japan which focused on low quality websites. The update resulted in certain websites moving down the results in the SERPs. 
+Japanese Google Webmaster Blog
+Search Engine Roundtable

PBN update or mass de-indexation - 01/02/2017

It has been reported within BlackHatWorld that this update aimed to target Private Blog Networks (PBNs), with some webmasters who use this SEO strategy expressing concern over changes to rankings since the 1st February.
+Search Engine Roundtable

Unnamed Major Update (Groundhog) - 01/02/2017

It has not been confirmed by Google, but a number of tracking tools report activity surrounding an update within the last 48 hours. However, there has been little discussion about these changes amongst webmasters. Black hat forums were much more active in relation to this update, particularly in the BlackHatWorld forum where it was suggested that this update could be targeting PBNs (Private Blog Networks).
+Go Fish Digital
+Search Engine Roundtable

Mobile Intrusive Interstitial Penalty - 10/01/2017

This penalty is only applicable to intrusive interstitials which occur directly after following a mobile search result to a specific web page. The update does not penalise or impact pages after this. If you have an intrusive interstitial which appears later in the click path on your website, this will remain unaffected. Only intrusive interstitials that link directly from the SERPs will be affected.
+Search Engine Land
+Search Engine Journal
+G-Squared Interactive

Unnamed Update - 05/01/2017

From Glenn Gabe over at G-Squared Interactive:

Since the autumn of 2016 a series of updates were implemented in a very short period of time. Since then, early indications have shown that Google may be increasing the frequency of their 'quality updates'. At the beginning of 2017, this pattern has only continued. Here are a series of core ranking updates which have focused on quality in the beginning of 2017:

• 5 January 2017
• 7 February 2017
• 7 March 2017 (Fred)
• 26 April 2017
• 4 May 2017
• 17 May 2017

Did you notice anything interesting? The updates seem to have changed from every few months to at least once a month or on occasions, even more frequently than this.

Unnamed Major Update - 14/12/2016

Several Google trackers reported a substantial flux between the 14 and 15 December including a rare, MozCast temperature of 109°F. A lot of activity was reported in the community as well but Google did not confirm that an update had taken place.
+Search Engine Roundtable

Unnamed Major Update (part 2 of 2) - 18/11/2016

On 10th November and again on 18th November a major spike (106°) was detected by MozCast. Discussion in the industry was high on both occasions, with some suggesting that the second spike was a reversal of the update that had taken place first. Google did not confirm either event. It was suggested by Glenn Gabe that the changes may have been as a result of Google testing the mobile-first index and then rolling it back. 
+G-Squared Interactive
+Search Engine Roundtable

Unnamed Major Update (part 1 of 2) - 10/11/2016

A major spike was detected by MozCast on both 10th November and again on 18th November. Considerable industry chatter was reported on both occasions with some suggesting that the second spike was to reverse the effects of the first update. Google however did not confirm anything. Glenn Gabe did state that it was possible that it was Google testing their mobile-first indexation which was then rolled back.
+G-Squared Interactive
+Search Engine Roundtable

Penguin 4.0, Phase 2 of 2 (#12) - 06/10/2016

A reversal of all previous Penguin penalties marked the launch of the second phase of Penguin 4.0. This seemed to occur after the new code was implemented and may have taken as long as two weeks. Activity post Penguin had one final peak which happend around 6th October. However it is not certain whether this was Penguin or a new update. Algorithm flux finally started to reduce after 6th October.

Penguin 4.0, Phase 1 of 2 (#11) - 27/09/2016

The first stage of Penguin 4.0 may have been launched between the 22 and 23 September and this was the implementation of a new, gentler Penguin algorithm which devalued bad links rather than penalising websites. Although the exact timeframe for this update has not been confirmed, it is believed that this rollout took a good few days to fully update and may have been related to an algorithm Moz temprature spike (113°) on 27th September.
+Moz

Penguin 4.0 Announcement (#10) - 23/09/2016

After almost two years the eagerly anticipated announcement was made by Google concerning a major Penguin update. It was suggested that Penguin is now real time and embedded into the 'core' algorithm. Initial impact assessments were small but it was later discovered that the Penguin 4.0 rollout was unusually long and occured in multiple phases (see 27th September and 6th October).
+Google
+Forbes
+Search Engine Land
+Moz - Rand Fishkin
+Moz - Dr. Pete

Image / Universal Drop - 13/09/2016

It was recorded by MozCast a nealy record 111° temperature and a 50% drop in SERPs with image (universal/vertical) results. The changes to universal results opened up an organic position on page 1 resulting in significant ranking shfits. It was said however this was likely to be part of a much larger update.
+Moz

Unnamed Update - 02/09/2016

Early indications this morning show that changes are taking place in the core web search results. Within the SEO community there are some indications of a possible update. It seems that there were two key updates in the last twenty four hours. A significant update based around core web search began early this morning or late last night. The second update was (local) Possum. 
+Search Engine Rountable
+Search Engine Land

Possum 1 - 01/09/2016

Although it was unconfirmed by Google, extreme temperatures were recorded by MozCast (measuring 108°). In addition to this there was a drop in local pack prevalance and the local SEO community reported a significant change in pack results. The data suggested that this update (or a simultaneous one) also had a dramatic impact on results in organic search.
+Search Engine Land
+Search Engine Land
+Quicksprout

Unnamed Update - 02/08/2016

This morning reports emerged in relation to changes and fluctuations in the Google search results. Some were saying that these changes occurred following after the reversal of an update which was implemented a week ago.
+Search Engine Roundtable

Unnamed Update - 27/07/2016

In the last few days webmasters have been reporting and welcoming various shifts in their traffic from Google with some fluctuations in search results. 
+Search Engine Roundtable

Mobile Friendly #2 - 12/05/2016

On the Webmaster blog it was announced by Google that they will be enhancing the effects of the mobile friendly algorithm that was launched on 21 April 2015. Google announced that the update will begin in May and it would increase mobile friendly ranking signals. They added that if you already have a mobile friendly website, you do not have to be alarmed because you will not be affected by the latest update. When the update takes place, it will be implemented slowly so you won't see significant changes in relation to non-mobile friendly websites once the algorithm has been rolled out. 
+Google
+Search Engine Land
+Search Engine Land

Unnamed Major Update - 10/05/2016

MozCast and other Google weather trackers identified a historically rare week long pattern of activity surrounding algorithms including a 97 degree spike. Google did not confirm that an update had been carried out and no other explanation is available.  
+Search Engine Roundtable

AdWords Shake-up - 23/02/2016

Significant changes were made to Google in terms of AdWords after it was decided to remove the right hand column of ads entirely from the SERPs. The 4-ad top-blocks on commercial searches would be implemented instead. While this was an update that related to paid search, it did have substantial implications for the Click Through Rate (CTR) for both organic and paid search results, particularly in relation to competitive keywords.
+Moz
+The SEM Post

Unnamed Update - 16/01/2016

An additional Google update has been confirmed this weekend, but it is a core update rather than one related to Penguin. Google were quick to respond that this update was the same as last weekend, focusing on their core algorithm. 
+Search Engine Land

Unnamed Update - 08/01/2016

Over the weekend Google delivered a core ranking algorithm update. Given that this is a core algorithm update, there are no specific details to identify what changes were made but many webmasters reported a significant flux in rankings. When Google confirmed this update, it was announced that Panda had been incorporated into the main algorithm as was the case in the final quarter of 2015. Nevertheless, the Panda element is not running in real time and was not updated at the weekend. Furthermore, it is unclear at this stage if site owners and webmasters are going to experience Panda updates in a different way following on from the recent changes.  
+Search Engine Land
+Search Engine Land
+Searchmetrics
+Search Engine Roundtable
+Search Engine Roundtable

Phantom #3 - 19/11/2015

On a daily basis countless web pages are analysed by Google quality raters which aim to improve the quality of search results. An update to their detailed guidelines was made by Google on the 12 November 2015. Shortly after this, Searchmetrics reported substantial movement in their visibility data and ranking. Is it possible that this is a Phantom Update III emerging? It does appear that the search results have been changed to bring them in line with the updated guidelines. 
+Searchmetrics
+Search Engine Land

Hacked Spam - 05/10/2015

From the Google blog:

Google have been recently implementing a number of algorithmic changes to address hacked spam in the search results. A high number of legitimate websites are targeted by spammers and are used to engage in abusive behaviour. Typically this includes promotion of traffic to low quality websites, downloads of malware, porn and the marketing of counterfeit goods or illegal pharmaceutical drugs to name a few. 

Websites that do not put in place suitable best practices in terms of security can leave their websites being vulnerable to hackers. This can include government websites, universities, small business and company websites, restaurants, conferences and hobby organizations. Cyber criminals and spammers intentionally seek out these types of websites and inject web pages with malicious content to gain rankings and traffic in search engines. 

Consequently, Google are aggressively targeting hacked spam in order to safeguard webmasters and users. 

It is estimated that the algorithmic changes will affect approximately 5% of queries depending on the language. 

As a result, if your website exists in any hacked spam keyword niches but your site is a legitimate one, you could benefit form the SERPs 'de-cluttering' which will be favourable for your site. This will leave you in a much stronger position. 

+Google Blog

Panda 4.2 (#28) - 17/07/2015

Google stated that a refresh of Panda began over the weekend, but it will take months to fully implement. The roll out is being undertaken at a very slow pace. As a result any impact on your website will be gradual. The Panda algorithm is a site wide algorithm but some web pages may not see an immediate change. Google have added that this will affect between 2 and 3% of English language search queries. 
+Search Engine Land
+The SEM Post
+Search Engine Roundtable
+Search Engine Land

Phantom #2 - 03/05/2015

Following a number of reports relating to large scale ranking changes originally named 'Phantom 2', Google have acknowledged that a core algorithm change had taken place which targeted 'quality signals'. This update seems to have resulted in a broad impact but Google did not provide any specifics in relation to the nature of the signals. Looking back, it may be that this was the roll out of Rankbrain. 
+Search Engine Land
+CNBC

Rankbrain - 30/04/2015

26 October, 2015 - announcement date
A major announcement was made by Google who revealed that machine learning had been part of the algorithm for a number of months and it contributed to the third most influential ranking factor. It is believed that the actual launch occured at some stage in Spring 2015, which is why the update displays a different time to when the update was actually announced officially.
+Bloomberg
+Search Engine Land

Mobile Friendly #1 ("Mobilegeddon") - 21/04/2015

On 21 April 2015, a new, mobile friendly ranking algorithm was released by Google. This is designed to boost mobile-friendly pages in the search results pages. One of the most effective ways to prepare for this change is to identify whether Google considers your web pages to be mobile friendly by using its dedicated Mobile-Friendly Test Tool.
Further Reading:
+Google Blog
+Moz
+Search Engine Land
+Search Engine Land (Advanced)
+TechCrunch
+Forbes

Unnamed Update - 04/02/2015

It has been reported by many SERP trackers and webmasters that a significant flux in Google search engine results pages has occurred. Speculation has ranged from an update focusing on ecommerce through to one relating to mobile usability. It was originally thought that the update was linked to Panda, but Google confirmed that it was neither a Penguin or Panda update. They did however release a response to questions surrounding the potential update outlining that 'tweaks' were continuing but a specific update was not going to be announced.   
+Search Engine Roundtable

+Searchmetrics

Pigeon - rest of English speaking world - 22/12/2014

A Pigeon update has been released by Google to the rest of the English speaking world (with the exception of India). The major algorithm update rolled out by Google named Pigeon extended to the United Kingdom, Canada and Australia. The original update initially hit the United States in July 2014. An update was confirmed on the 22nd but it may have been rolled out as early as the 19th. 
+Search Engine Land
+BrightLocal
+Fat Media

Penguin 3.4 (#9) - 06/12/2014

This upate was part of the wider 3.0 implementation. Penguin updates aim to target websites which are thought to be spammy, particularly those who are violating guidelines from Google in relation to linking. 
+Search Engine Land

Penguin 3.3 (#8) - 05/12/2014

This was an update that formed part of the wider roll out of 3.0. Penguin updates specifically target websites which are classed as being spammy or they are violating Google guidelines in terms of linking. 
+Search Engine Land

Penguin 3.2 (#7) - 02/12/2014

Part of the 3.0 implementation, Penguin updates aimed to address websites that were using questionable linking practices and who violated Google guidelines.
+Search Engine Land

Penguin 3.1 (#6) - 27/11/2014

Part of the 3.0 implementation, this update was related to Penguin which aimed to target spammy websites, particularly those who were violating Google guidelines with poor linking strategies. 
+Search Engine Land

Pirate #2 - 21/10/2014

Over two years since the first DMCA/Pirate update, Google launched another update which aimed to address piracy of digital media and software. This update was very specific and resulted in a small group of sites experiencing a significant drop in rankings.
+Searchmetrics
+TorrentFreak

Penguin 3.0 - Everflux (#5) - 17/10/2014

Google implemented a Penguin refresh more than a year after the previous Penguin 2.1 Update. This update was much smaller than anticipated with less than 1% of US and English queries being affected. It was probably data only rather than a new Penguin algorithm. The timing of the update was also vague, especially on an international basis. Google claimed at the time that it was implemented over a number of weeks. 
+Search Engine Roundtable
+G-Squared Interactive

December 10, 2014
It was announced by a Google representative that Penguin had made the transition to continuous updates rather than infrequent and significant updates. Although the exact timescale for updates was unclear, this appeared to fit in with the ongoing flux that occurred following Penguin 3.0 which included unconfirmed reports of Penguin 3.1

+Search Engine Land

"In The News" Box - 10/10/2014

It seemed that Google had made a change to News box results. However it was later announced that they had expanded news links to a greater range of potential websites. News results in the SERPs also increased with major news websites reporting substantial changes in traffic. 
+Search Engine Land
+Search Engine Roundtable

Panda 4.1 (#27) - 26/09/2014

The latest version of the Panda update has been announced by Google. Panda was developed as a filter to penalise thin or poor content from ranking well in the SERPs. In a post on Google+, Google stated that the roll out was slow and it had begun earlier in the week. They added that the changes will continue into next week before completion soon after. Depending on location, between 3% and 5% of search queries will be impacted. Google said that the latest release was more precise to enable high quality, small and medium sized websites to rank more effectively. 
+Google Announcement
+Search Engine Roundtable
+Search Engine Land
+G-Squared Interactive

PBN mass de-indexation - 23/09/2014

Within Black Hat and Grey Hat communities, much discussion is taking place in relation to Google's efforts to target Private Blog Networks (PBNs). In the past few days, Google has targeted a number of PBNs that are being used to manipulate rankings. Google distributed hundreds, if not thousands of manual action notifications to those websites who were using this technique. 
+Search Engine Roundtable

Authorship Removed - 28/08/2014

After a drop in authorship photos on 28 June Google announced the complete removal of authorship markup. They also added that it would not be processed any more. By the following morning, many authorship bylines had completely disappeared from the SERPs. 
+Google
+Search Engine Land

HTTPS / SSL Update - 06/08/2014

Following many months of speculation, Google announced that they would give preference to secure websites. They added that encryption would provide a light boost to rankings. It was also stressed that this would start out small but it may increase if the change delivered positive results. 
+Google
+Search Engine Land

Pigeon (US Only) - 24/07/2014

Applicable to US search results only, Google transformed local SEO with an update which significantly affected some local search results and the way in which they processed location cues. Google claimed that Pigeon created more effective connections between the local and core algorithms. 
+Search Engine Roundtable
+Search Engine Land
+Search Engine Land
+Blumenthals

Authorship Photo Drop - 28/06/2014

A surpise announcement was made by John Mueller on 25 June to state that Google would be dropping all authorship photos from the SERPs. This was complete around 28 June. 
+Moz
+Search Engine Land

Payday Loan #3 - 12/06/2014

Google launched a major iteration less than a month following the Payday Loan #2 anti-spam update. Official statements highlighted that 2.0 specific sites while 3.0 focused on spammy queries.
+Search Engine Roundtable

Panda 4.0 (#26) - 19/05/2014

Confirmation from Google identified a major Panda update which very likely incuded both a data refresh and an algorithm update. Approximately 7.5% of search queries delivered in English were affected. Matt Cutts further added that it was being rolled out on 5/20, while over at Moz, it was suggested that the updates began much sooner than this.
+Search Engine Land
+Moz

Payday Loan #2 - 16/05/2014

Shortly before Panda 4.0, Google completed an update to its 'Payday Loan' algorithm which specifically targeted spammy queries. Although it was not clear when rollout was delivered exactly (Google had indicated 'this past weekend' on 20th May). Back-to-back updates meant that it was difficult to identify.
+Search Engine Land

Unnamed Update - 24/03/2014

A spike in webmaster chatter combined with major algorithm flux trackers between the 3/24 and 3/25 resulted in speculation that a new 'softer' Panda update had been delivered. A number of websites reported changes to their rankings but this update was not confirmed by Google.  
+Search Engine Roundtable
+G-Squared Interactive

Top Heavy #3 - 06/02/2014

Matt Cutts, Google's head of search spam made an announcement to say that Google had carried out a refresh of its Page Layout Algorithm. This filter, also referred to as a Top Heavy algorithm pushes websites further down the SERPs where there are too many advertisements at the top of the page or if the ads are considered to be distracting for users.
+Search Engine Land

Authorship Shake-up - 19/12/2013

Over a period of approximately a month, authorship markup was eliminated entirely from around 15% of search queries as predicted by Matt Cutts at Pubcon Las Vegas. The fall bottomed out around 19 December, but the numbers remained fluid and had not recovered to earlier levels.
+Moz
+Hive Digital

Unnamed Update - 17/12/2013

The majority of global flux trackers reported historically high levels of activity. Google would not confirm an update suggesting that they avoid updates near the holidays. In addition, a rise in some Partial Match Domains (PMDs) were reported by MozCast but the patterns were quite vague.
+Dejan Marketing
+Search Engine Land

Unnamed Update - 14/11/2013

A number of Google trackers highlighted unusual activity which occurred at the same time as reports relating to widespread DNS errors in Google Webmaster Tools. Google did not confirm an update at the time and the nature and cause of this flux remained unknown.
+Moz
+Search Engine Roundtable

Penguin 2.1 (#5) - 04/10/2013

Following a 4 and a 1/2 month gap, another Penguin update was launched by Google. With a 2.1 designation it was likely that this was primarily a data update rather than a significant change to the actual Penguin algorithm. The overal impact did appear to be moderate but some webmasters reported that they had been hit hard.
+Search Engine Land
+Search Engine Roundtable

Mugshot Update - 03/10/2013

Arrest information and photographs from US government websites were picked up by Mugshot sites. This data was then used to create landing pages which will rank effectively in the search engine results pages. When an individual then searches for their own name and sees the result, it is likely that they will pay to have it removed. Websites charge anywhere between $30 and $400 to remove the page and there are multiple sites that they need to pay to have their information removed. More often than not, arrests did not lead to a trial or a guilty charge but the web pages don't provide this level of detail. Google has however, taken proactive steps to stop these mugshot websites from ranking so highly in the SERPs.
+Search Engine Land

Hummingbird - 20/08/2013

Google announced the release of Hummingbird on 26 September, and suggested that it had been rolled-out the previous month. It is likely that this was around the time when there was a MozCast spike and a number of reports of flux between 20 and 22 August. Hummingbird has been likened to Caffeine and appears to be a core algorithm update which may power a series of changes to semantic search and the Knowledge Graph for months to come.
+Search Engine Land
+Search Engine Roundtable

In-depth Articles - 06/08/2013

A new type of news result has been added by Google which focuses on in depth articles targeting long form, evergreen content. When it was launched, it included links to three articles and appeared in approximately 3% of tracked searches by MozCast.
+Google
+Moz

Unnamed Update - 26/07/2013

A significant spike (105° F) was tracked on Friday by MozCast with other sources reporting significant activity over the weekend. Google did not confirm that an update had taken place.
+Search Engine Roundtable
+Moz Google+

Knowledge Graph Expansion - 19/07/2013

It appeared that almost overnight, queries in relation to Knowledge Graph (KG) entries increased by more than half (+50.4%) within the MozCast data set. Furthermore, over a quarter of all searches identified some form of KG entry.
+Moz

Panda Recovery (Detuning) - 18/07/2013

A Panda update was confirmed by Google although it was unclear whether this was part of a wider schedule of 10-day rolling updates or whether it was something completely new. It was suggested that this was algorithmic and intended to soften some of the previous penalties that resulted from Panda.
+Search Engine Roundtable

Multi-Week Update - 27/06/2013

A reply was tweeted by Matt Cutts from Google that suggested a multi week algorithm update that would take place between 12 June and the week after 4 July. The specifics of the update remained unclear but there were significant changes in rankings during that period which peaked on 27 June (as reported by MozCast data). It seemed that Google had been carrying out some tests in relation to proposed changes, but these were later rolled back.
+Moz
+Search Engine Roundtable

Payday Loan #1 - 11/06/2013

An update from Google that aimed to target a range of 'spammy queries'. These included those in niches such as payday loans, pornography and other heavily spammed queries. At SMX Advanced, Matt Cutts outlined that the update focused on unique link schemes which go against Google guidelines. He also added that this worldwide update rather than one restricted to the US. Approximately 0.3% of US search queries were affected by the update, while 4% of Turkish queries were impacted where web spam is higher. This is a multi-faceted roll out which is expected to occur over the next one to two months.
+Search Engine Land
+Search Engine Roundtable

Penguin 2.0 (#4) - 22/05/2013

Following several months of speculation the 4th Penguin update (referred to as 2.0 by Google) arrived but the impact was moderate. The specific details of the changes that were made remained unclear, but some evidence suggested that Penguin 2.0 was targeted at page level. That being said there was a twist to Penguin 4. This was because the update contained Penguin 2.0 technology which Google added was a new generation of technology that would stop spam more effectively.
+Search Engine Land
+Moz

Domain Crowding (SERP Clustering #3) - 21/05/2013

An update to domain crowding and diversity deep in the SERPS (beyond page 2) was released by Google. The timing of this update remained vague but it was suggested it was rolled out shortly before Penguin 2.0 in the US and perhaps even the same day on an international basis. Matt Cutts explained that once a cluster of approximately four results from a specific domain has been seen, subsequent pages are less likely to show you results from that domain name.
+Briggsby
+Search Engine Land

Phantom #1 - 09/05/2013

Around 9 May a series of reports appeared to indicate that there had been an algorithm update. The specifics of this update was not known but many sites reported significant losses in terms of traffic.
+Search Engine Roundtable
+G-Squared Interactive

Panda #25 - 14/03/2013

At SMX West it was pre-announced by Matt Cutts of a Panda update and it was suggested that it would be the last update before Panda was integrated into the core algorithm. Although exact dates were unconfirmed, it was anticipated that it would take place either on the 13th or the 14th.
+Search Engine Roundtable
+Search Engine Land

Panda Dance — 11 June 2013 Although this was not an actual update to Panda, Matt Cutts provided crucial clarification at the SMX Advanced. It was suggested that Panda was still being updated on a monthly basis and each update was being implemented over the course of a 10 day period. This was not the everflux that had been expected following Panda #25.  
+Search Engine Land

Panda #24 - 22/01/2013

The first official update of 2013 was announced by Google who claimed that 1.2% of search queries were affected. However, this did not seem to be related to discussion around the 1/17-18 which remained unconfirmed by Google.
+Search Engine Roundtable
+Search Engine Land

Panda #23 - 21/12/2012

Rumors of a Google update were confirmed by Google who announced on Twitter that a Panda refresh would be pushed out today. Approximately 1.3% of English search queries would be affected.
+Search Engine Roundtable

Knowledge Graph Expansion - 04/12/2012

Non-English queries had been added by Google to Knowledge Graph functionality. This included Italian, Russian, Spanish, French, German and Portuguese. However, the update was much more than simply translation and served to enhance the capabilities of the Knowledge Graph.
+Google
+TechCrunch

Panda #22 - 21/11/2012

The Panda 22 (data refresh) was announced by Google and it affected 0.8% of search queries in English, perhaps to the extend that a regular user may notice. This is slightly lower than Panda 21 which was released on 5 November which impacted 1.1% of English search queries.
+Search Engine Roundtable
+Search Engine Land

MetaFilter - 17/11/2012

MetaFilter announced in May 2014 that they had been hit by an algorithm update but this did not correspond particularly well with any of the well known algorithm filters or updates. However, it has now been confirmed in June 2014 by Google that MetaFilter was hit by a different algorithmic filter and Google are trying to rectify the MetaFilter false positive later on in 2014. MetaFilter is perhaps a vulnerable site that many early internet users remember with fondness before the likes of Facebook, Twitter, BuzzFeed and Reddit appeared, bombarding us with quizzes, articles and endless posts. The update that was rolled out from 17 November 2012 appears to have significantly impacted on forum based websites.
+Search Engine Roundtable
+Search Engine Land
+Search Engine Land

Panda #21 - 05/11/2012

On a worldwide basis, Google stated that the update will affect approximately 0.4% of search queries that would be noticed by a regular user. For those who were searching in the United States and using the English language, this percentage is slightly higher at 1.1% according to Google. This marks the 21st confirmed Panda update and reflects the 4-6 week release schedule.
+Search Engine Land
+Search Engine Roundtable

Top Heavy #2 - 09/10/2012

A refresh of the Page Layout Filter was announced by Google for a second time following the initial announcement in January. Known as the Top Heavy update, the algorithm targets websites where there are too many adverts above the fold. This update is the second that has been confirmed of its kind in Google's ranking system. The update rolled out on 19 January 2012 impacted less than 1% of English search queries. The second update on 9 October 2012 impacted 0.7% of English search queries.
+Search Engine Land
+Search Engine Roundtable

Penguin 1.2 (#3) - 05/10/2012

The head of Google's spam team, Matt Cutts released a series of tweets about the Penguin update. The first of these stated that a refresh to Penguin was on its way and approximately 0.3% of English search queries would be noticeably affected.  Spanish impact would be ~0.4% while the Italian impact would ~0.3% of all search queries.
+Search Engine Land
+Search Engine Roundtable

August/September 65-Pack - 04/10/2012

The monthly list of search highlights was published by Google and it listed 65 updates for August and September. These updates featured 7 result SERPs, an expansion to Knowledge Graph, updates to page quality calculations and changes to the way in which local search results were determined.
+Google

Exact-Match Domain (EMD) Update - 28/09/2012

Google made an announcement that they were changing the way Exact Match Domains (EMDs) were going to be handled. This resulted in a large scale devaluation which reduced the presence of Exact Match Domains by more than 10%. Official word was that approximately 0.6% of search queries were affected.
+Moz
+Search Engine Land

Panda #20 - 27/09/2012

On Thursday, the 27 September, Google began to implement a new update to Panda. Rather than being an actual data update this was an update to the Panda algorithm. A series of notable differences occurred on Thursday even though the full roll out will take a further 3 to 4 days. This update is expected to affect approximately 2.4% of English search queries and to an extent where a regular user may notice changes. Search queries in other languages have not felt the impact as much. 
+Search Engine Roundtable
+Search Engine Roundtable

Panda 3.9.2 (#19) - 18/09/2012

An additional Panda update has been announced by Google and it is expected that approximately 0.7% of search queries will be impacted as a result. With the roll out of the Panda refresh webmasters should see some flux in the coming days.
+Search Engine Roundtable
+Search Engine Land

SERP Diversity (SERP Clustering #2) - 14/09/2012

It has been noticed recently that Google search results can sometimes seem to be dominated by web pages from the same domain. Matt Cutts the Head of Google's spam team released a tweet explaining the update as a small algorithm change to improve the diversity of search results and range of domains that are listed in the SERPs. This update also partly reversed the effects that resulted from the 'Brand update' carried out on 31 August 2010.
+Search Engine Land

Panda 3.9.1 (#18) - 20/08/2012

A further Panda data update was rolled out by Google, but the impact appeared quite small. The Panda 3.0 series did run out of numbers once it reached 3.9 so the latest update was called 3.9.1.
+Search Engine Roundtable
+Search Engine Land

7-Result SERPs - 14/08/2012

A significant change was made to the Top 10 by Google, limiting it to just 7 results for the majority of queries. Research found that this change was implemented over a couple of days and had an effect on approximately 18% of keywords tracked by Moz.
+Moz
+Search Engine Land

DMCA Penalty "Pirate" (#1) - 11/08/2012

Starting from next week commencing the 13 August, Google had announced that sites with repeat violations of copyright, primarily through DMCA takedown requests would be penalised.
+Google
+Search Engine Land

June/July 86-Pack - 10/08/2012

The Search Quality Highlights were delivered as one post following a summer break. Some of the major updates included one to Panda data and a series of algorithm refreshes in addition to an improved rank ordering function and a boost in ranking for sites from 'trusted sources' as well as changes to clustering.
+Google
+Search Engine Land

Panda 3.9 (#17) - 24/07/2012

A new Panda update was rolled out a month after Panda 3.8. As a result, rankings fluctuated for 5 to 6 days although none of these days showed results that stood out amongst the rest. It was claimed by Google that ~1% of queries were impacted.
+Search Engine Roundtable

Panda 3.8 (#16) - 25/06/2012

A further Panda data refresh was rolled out but this focused on data only rather than the actual algorithm and it had a much smaller impact than Panda 3.7.
+Search Engine Land
+Search Engine Roundtable

Panda 3.7 (#15) - 08/06/2012

An additional update was rolled out by Google in relation to Panda, but less than 1% of search queries were affected. Data in relation to fluctuations in rankings suggested that the impact was considerably higher than the previous updates delivered through Panda 3.5 and 3.6.
+Search Engine Roundtable
+Moz

May 39-Pack - 07/06/2012

Following the release of their monthly Search Highlights, Google stated that 39 updates had been carried out in May. Some of the significant changes included improvements to Penguin, enhanced detection of link schemes, title and snippet rewriting changes and further updates to Google News.
+Google
+Search Engine Land

Penguin 1.1 (#2) - 25/05/2012

Following the Penguin algorithm update, Google implemented its first targeted data update which confirmed that the processing of Penguin data was taking place outside of the main search index, very similar to data in Panda.
+Search Engine Land

Knowledge Graph - 16/05/2012

As a further step toward semantic search, Google began to roll out Knowledge Graph. This was an integrated display in the SERPs that provided additional information about people, places and things. As time progresses you will begin to see more and more knowledge panels appear in the search results.
+Google
+Search Engine Land

April 52-Pack - 04/05/2012

A list of 52 updates and corresponding details was published by Google from April which included several changes linked to the Penguin update. Other updates included a larger base index (by 15%), site links updates and improved handling of pagination.
+Google
+Search Engine Land

Panda 3.6 (#14) - 27/04/2012

Less than a week after Panda 3.5 was released, Google delivered another update. The implications of this update were unknown but it appeared that any effects were minimal.
+Search Engine Land

Penguin (#1) - 24/04/2012

Following many weeks of speculation surrounding a penalty relating to over optimisation, Google rolled out the Webspam update. This was shortly renamed to Penguin. A number of spam factors were addressed by Penguin including keyword stuffing. It was estimated that approximately 3.1% of English search queries were affected.
+Google
+Search Engine Land
+Search Engine Land
+Search Engine Land

Panda 3.5 (#13) - 19/04/2012

This week marked a busy time for the algorithm, Google quietly released another Panda update. A combination of changes made the impacts of this update quite difficult to measure but it appeared to be a routine update with little impact.
+Search Engine Roundtable

Parked Domain Bug - 16/04/2012

A series of shuffles in ranking were reported by webmasters and Google confirmed that there had been a data error. This error resulted in some domains being mistakenly classed as 'parked domains' and consequently they were devaluated. This was not an intentional change to the algorithm.
+Search Engine Land
+Search Engine Roundtable

March 50-Pack - 03/04/2012

In its latest publication, Google delivered a batch of update highlights that identified 50 changes that occurred in March. These changes included a confirmation that Panda 3.4 had been released as well as additional changes to anchor text scoring, an update on the image search and changes to the way in which queries were interpreted.
+Google
+Search Engine Land

Panda 3.4 (#12) - 23/03/2012

An announcement was made by Google on Twitter in relation to a new Panda update which was being rolled out. Within the public statement it outlined that approximately 1.6% of search results would be affected by Panda 3.4.
+Search Engine Land

BuildMyRank de-indexation - 19/03/2012

Efforts to reduce web spam resulted in many link networks being de-indexed including Build My Rank. +more info

Venice (local search) - 28/02/2012

Within the monthly update Google mentioned a code name 'Venice'. This was a local update which was used to localise (aggressively) organic results and facilitate the integration of local search data. The exact date of the roll out was unclear.
+Moz
+Catalyst eMarketing

Panda 3.3 (#11) - 27/02/2012

A relatively minor, post flux Panda update was rolled out which occurred three days after the 1 year anniversary of Panda. This was an unprecedented period of time for a named update.
+Search Engine Land
+Search Engine Roundtable

February 40-Pack - 26/02/2012

A second set of 'Search Quality Highlights' at the end of the month was published by Google which listed more than 40 charges in February. Key changes included updates to image searches, multiple image searches, several freshness updates (that included 2 sections of the old algorithm being phased out completely) as well as the Panda update.
+Google

Top Heavy (#1) - 19/01/2012

This update impacted fewer than 1% of global searches. Google took a number of steps to improve search results and they launched an algorithmic change which looks specifically at web page layout and the content that you see on the page when you click through to the website from the results page. This change does not impact any sites who use ads above the fold to a certain degree but it did affect sites where there are so many ads at the top of the page it can be difficult to identify the main content on the page. This improvement to the algorithm affected websites where only a small amount of content is visible above the fold or relevant content is pushed further down the page in favour of advertisements.
+Google
+Search Engine Land

Panda 3.2 (#10) - 18/01/2012

Although Google had confirmed there was a Panda update, they did suggest that there had been no changes to the algorithm. It was however uncertain how this update fitted into the 'Panda Flux' in recent data updates that occurred more often.
+Search Engine Roundtable
+Search Engine Land

Search+ Your World - 10/01/2012

A significant shift in personalisation was announced by Google. This update aggressively moved Google+ social information and user profiles into the SERPs. There was also an addition of a new, toggle button to switch off personalisation.
+Google
+Search Engine Land

January 30-Pack - 05/01/2012

Over the previous month, 30 changes were reported by Google which included the quality of landing pages in relation to image searches, site links which were more relevant, additional rich snippets and a range of improvements to related queries. However, the difference between features and algorithm updates did become less clear. 
+Google
+Search Engine Land

December 10-Pack - 01/12/2011

A second set of 10 updates were outlined by Google and it was announced that these posts would be released every month. The updates included a variety of changes including query refinements, detection of parked domains, freshness of blog and image searches. The exact dates of the updates however remained unknown.
+Google
+Search Engine Land

Panda 3.1 (#9) - 18/11/2011

Once Panda 2.5 had been rolled out, a period of 'Panda Flux' emerged on Google. During this time, updates began to occur more often although they were minor changes. Some industry experts called the update on the 18 November 3.1, even though officially 3.0 hadn't been released.
+Search Engine Roundtable

10-Pack of Updates - 14/11/2011

This was said to be one of the more unusual updates. Matt Cutts published a post that listed the 10 most recent updates to the algorithm in an attempt to be more transparent. It isn't exactly clear what the original timescale was and most of the updates were relatively minor. That being said, it did demonstrate a change in how Google communicated changes to algorithms.
+Google
+Search Engine Land

Freshness Update - 03/11/2011

An announcement from Google stated that an algorithm change had taken place which favoured freshness and this would affect up to 35% of search queries. This was up to 3 times the impact of Panda 1.0. The update affected time sensitive search queries but placed great emphasis on content that was up to date.
+Google
+Search Engine Land

Query Encryption (Not Provided) - 18/10/2011

It was announced by Google that search queries would be encrypted, primarily for reasons surrounding privacy. Unfortunately this had a detrimental impact on organic keyword referral data, delivering 'not provided' for certain types of organic traffic. Following its launch this number only increased in the weeks that followed.
+Google
+Moz

Panda Flux (#8) - 05/10/2011

Through a Tweet by Matt Cutts, it was reported that there would be a flux that related to Panda in the coming weeks, but this would be ~2%. A series of Panda updates, albeit minor were rolled out on the 3 October, 13 October and 18 November respectively.
+Search Engine Land
+Search Engine Land

Panda 2.5 (#7) - 28/09/2011

Google rolled out another update to Panda after more than a month. The details of the exact changes were unclear, but some websites reported significant losses.
+Search Engine Land
+Search Engine Land

Pagination Elements - 15/09/2011

Link attributes rel=next and rel=prev were introduced by Google in an attempt to fix duplication and crawl issues created by pagination. An announcement was also released stating that canonicalisation and automatic consolidation had been improved for 'View All' pages.
+Google
+Search Engine Land

Expanded Sitelinks - 16/08/2011

Following a period of experimentation, Google officially implemented expanded site links predominantly for brand related queries. Initially these were 12 packs but it appeared that Google had restricted this to 6 soon after the update was rolled out.
+Google
+Search Engine Land

Panda 2.4 (#6) - 12/08/2011

Panda was rolled out on an international basis both for global English and non-English queries. This was with the exception of queries in Chinese, Japanese and Korean. In the affected countries between 6% and 9% of search queries were impacted.
+Google
+Search Engine Land

Panda 2.3 (#5) - 23/07/2011

Increased discussion amongst Webmasters indicated that another update had been rolled out by Google. It was unclear what the changes involved or whether it was simply an update to Panda data and ranking factors.
+Search Engine Land
+Stone Temple

Google+ - 28/06/2011

Following a series of failures on social media, Google began a serious attack on Facebook with the launch of Google+. This new social media platform was based around circles for sharing content and was closely integrated into Google related products such as their Gmail feature. Social 'pioneers' were quick to sign up and after just 2 weeks, Google+ had 10 million users.
+Google
+TechCrunch

Panda 2.2 (#4) - 21/06/2011

As Version 2.2 was officially acknowledged, Google continued to update sites that had been affected by Panda. The Panda updates happened independently from the main index and they were not undertaken in real time.
+Search Engine Land
+Search Engine Land

Schema.org - 02/06/2011

Confirmation came from Yahoo, Google and Microsoft in relation to a consolidated approach to structured data. A series of new 'schemas' were also introduced in an attempt to enhance search results and improve accuracy for web users.
+Search Engine Land

Panda 2.1 (#3) - 09/05/2011

Another set of changes were rolled out by Google which were initially called Panda 3.0. These changes weren't covered in detail by Google and they appeared to be particularly minor in nature.
+Search Engine Land
+Search Engine Roundtable

Panda 2.0 (#2) - 11/04/2011

The Panda update was rolled out to cover all English search queries globally and it was not restricted to English speaking countries. A number of new signals were also integrated which included information about site users blocked through the SERPs, either through the Chrome browser or directly.
+Google
+Search Engine Land

The +1 Button - 30/03/2011

In response to competition by several social media platforms including Twitter and Facebook, Google released their +1 button which was displayed directly next to results links. When users clicked on the +1 button, search results could be influenced within their social circle, both in relation to paid and organic search results.
+Search Engine Land

Panda / Farmer (#1) - 23/02/2011

Up to 12% of search results were affected by a significant algorithm update. Panda aimed to tackle content farms, thin content, websites with high ad-to-content ratios and addressed a series of other quality related issues. Panda was due to be rolled out over a couple of months, heading to Europe in April 2011.
+Wired
+Moz

Attribution Update - 28/01/2011

Following a series of high profile spam cases, Google responded with an update to remedy content attribution and prevent scrapers. It was reported by Matt Cutts that approximately 2% of search queries were affected.
+Matt Cutts

Negative Reviews - 03/12/2010

An expose in the New York Times described how DecorMyEyes, an ecommerce based website had managed to rank based on negative reviews. This resulted in Google adjusting the algorithm to prevent websites using similar tactics from ranking well in the SERPs.
+Google
+The New York Times

Social Signals - 01/12/2010

It was confirmed by both Google and Bing that social signals were used to determine ranking and this included data from Facebook and Twitter. Confirmed by Matt Cutts, this was a relatively new development, but it was something that had been expected for a long time by SEO specialists.
+Search Engine Land
+Search Engine Land

Instant Previews - 09/11/2010

Within the Google search results, a magnifying glass appeared. This allowed web users to quickly preview landing pages directly from the SERPs. This highlighted a renewed emphasis by Google on the quality of landing pages as well as design and usability.
+Google

Google Instant - 30/09/2010

Building on Google Suggest, Google Instant was released which displayed the search results as the user typed in their query. The impact however only proved to be very small.
+Moz

Brand Update (SERP Clustering #1) - 31/08/2010

Google began to allow multiple appearances for the same domain within the SERP. Before this was released, domains were restricted to 1 or 2 listings, or perhaps 1 listing with other results displayed underneath but indented to indicate they were from the same site.
+Search Engine Land

Caffeine - 08/06/2010

Google completed their roll-out of the Caffeine infrastructure following months of testing. This update not only increased Google's speed, but it integrated indexation and crawling more effectively which resulted in a fresher index. According to Google freshness improved by 50%.
+Google Blog
+Search Engine Land
+The Register

May Day - 01/05/2010

Webmasters identified a substantial drop in their long tail traffic toward the end of April and into May. It was later confirmed by Matt Cutts that May Day was an algorithm change which affected long tail. Websites that featured lots of thin content were hit particularly hard and this was even more so with the Panda update.
+Search Engine Land
+Search Engine Roundtable

Google Places - 15/04/2010

The 'Places' feature was rolled out in 2009 but it was originally a component of Google Maps. When Google Places was officially launched this re-branded the Local Business Centre and Places pages were integrated more effectively. Local search results and a series of new features were added including options for local advertising.
+Search Engine Land
+Google

Real-Time Search - 15/12/2009

A number of real time feeds were integrated into the SERPs from websites such as Twitter and Google News. Sources continued to expand over time and included more 'real time' social media feeds.
+Search Engine Land

Caffeine (Preview) - 15/08/2009

A preview of a huge infrastructure change was released by Google. This was designed to increase the index and improve indexation and ranking so that they were in real time. The timeline for this update spanned a number of months, with the final implementation beginning in the US in the early part of 2010 and running until the summer. 
+Mashable
+Google

rel=canonical tag - 15/02/2009

Joint support from Google, Microsoft, and Yahoo was announced in relation to the Canonical Tag. This enabled webmasters to send canonicalisation signals to search bots without it having an impact on human web visitors.
+Matt Cutts
+Moz

Vince - 15/02/2009

A number of SEOs reported that a significant update was released that favoured high profile brands. This update, Vince was deemed to be a minor one by Matt Cutts, but many SEOs felt that the effects would be profound with lasting implications.
+SEO Book
+Search Engine Land

Google Suggest - 15/08/2008

Google Suggest was introduced in a major change to their logo and a box home page. This displayed suggested searches in a dropdown box below the main search bar where the web user typed in their search query. This Google Suggest would later go on to power what eventually evolved into Google Instant.
+Search Engine Land

Dewey - 25/04/2008

Toward the end of March and into early April, a significant shuffle took place but specific details about any update were unclear. Some suspected that it was something to do with Google pushing its own internal properties including Google Books, but there wasn't substantial evidence to support this theory.
+Search Engine Roundtable

Buffy - 15/07/2007

To honour the departure of Vanessa Fox from Google, this update was dubbed Buffy. Although no one quite understood what actually happened, but Matt Cutts confirmed that Buffy was a series of minor changes.
+Matt Cutts
+Search Engine Roundtable

Universal Search - 15/05/2007

Although it was not your average algorithm update, Google began to integrate news, video, local and a range of other options into the traditional search results which substantially altered the format. The old SERP that displayed 10 listings ceased to exist.
+Search Engine Land

False Alarm - Unconfirmed Update - 15/12/2006

In December, there were signs of an update as well as reports of significant ranking changes in November, but Google didn't report any major changes at the time.

Supplemental Update - 15/11/2006

It appeared that Google had made changes to the way in which filtered pages were managed and the supplemental index throughout 2006. Although it felt like it was a penalty, it was claimed late in the year that it was not.
+Search Engine Roundtable

Big Daddy - 15/12/2005

Similar to the more recent Caffeine update, Big Daddy was more of an infrastructure update which concluded at the end of March 2006. Big Daddy completely changed the way in wihch URL canonicalisation and 301/302 redirects were handled by Google, as well as addressing a range of other technical issues.
+Matt Cutts
+Moz

Google Local/Maps - 20/10/2005

Following the launch of the Local Business Centre in March 2005 and emphasis on encouraging businesses to keep their information up to date, Google carried out a merger which combined its maps into the local business centre. This was a move which would initiate a series of changes in local SEO.
+

Jagger - 15/10/2005

A number of updates were released to target low quality linking issues such as reciprocal links, paid links and link farms. The Jagger update was implemented in three stages between September and November 2005, with the greatest impact being felt in October.
+Search Engine Roundtable
+Webmaster World

Gilligan - 15/09/2005

Gilligan was also referred to as a false update where webmasters saw ongoing changes. Google claimed that there hadn't been any major algorithm updates. In a blog post, Matt Cutts outlined that Google had updated the index of daily data but the Toolbar PR and other metrics had only been updated once in three months.
+Search Engine Watch
+Matt Cutts

Personalized Search - 15/06/2005

Personalised search that was rolled out in 2005 aimed to tap into user search history to adjust the search results automatically. This update was unlike any previous attempt at personalisation. Initially the impact was small, but Google went on to use search history for a number of applications.
+Search Engine Watch
+Google

XML Sitemaps - 15/06/2005

This update enabled the submission of XML sitemaps through Webmaster Tools which bypassed traditional HTML sitemaps and providing SEOs a little influence over indexation and crawling.
+Search Engine Watch

Bourbon - 15/05/2005

A number of changes were being rolled out in relation to search quality. Although no one was quite sure about what the change was exactly, Webmaster World members speculated that Bourbon had changed the way in which non-canonical www. vs. non-www. URLs and duplicate content were processed.
+John Battelle's Search Blog
+Search Engine Roundtable

Allegra - 15/02/2005

Ranking changes were witnessed by webmasters, with some suggesting that the update Allegra had affected the Sandbox while others believed that it was the LSI that was impacted. There was also speculation as to whether suspicious links were being penalised.
+Search Engine Watch

Nofollow - 15/01/2005

In an attempt to eliminate spam and strictly control the quality of outbound links, Google, Yahoo and Bing collaboratively introduced what is known as the no-follow attribute. This helps to clean up poor links such as spammy blog comments. Although this was not a traditional algorithm update, it did have a substantial impact on the link graph.
+Search Engine Watch

Brandy - 15/02/2004

A series of changes were rolled out by Google which included a huge index expansion. Latent Semantic Indexing (LSI) served to increase the focus on the relevance of anchor text and the idea of link neighbourhoods. LSI improved the ability of Google to understand related words and phrases (synonyms) and enabled keyword analysis to progress to the next level.
+webpronews.com
+SitePoint

Austin - 15/01/2004

Any issues that were overlooked by the update 'Florida' were addressed by Austin. Google continued to tackle on page strategies that proved to be deceptive including meta tag stuffing and invisible text. There was some speculation that Google had implemented the Hilltop algorithm and began to take page relevance very seriously.
+Search Engine Journal
+Search-Marketing.info

Florida - 15/11/2003

As one of the more prominent updates, this was perhaps the one that put the SEO industry on the map. A number of websites lost their rankings following-on from this update, and business owners were furious. Florida effectively eliminated many of the SEO strategies from the 1990s including keyword stuffing, and made the SEO landscape far more interesting .
+Search Engine Watch

Supplemental Index - 15/09/2003

In an attempt to index documents without impacting on performance, Google separated some results into what was known as a supplemental index. The dangers of having results move into the supplemental index was a hotly debated SEO topic until the index was later re-integrated.
+Search Engine Watch

Fritz - 15/07/2003

Fritz brought to an end the monthly Google Dance. Rather than entirely overhauling the index on a monthly basis, Google changed this to an incremental approach. As a result, the index now changed on a daily basis.
+Matt Cutts explains algo updates and data refreshes
+Wired exclusive

Esmeralda - 15/06/2003

Esmeralda was the last of the monthly updates from Google and a more continouous process started to emerge. Everflux replaced the Google Dance and it was the Esmeralda update that signalled the start of some major infrastructure changes for Google.
+Webmaster World

Dominic - 15/05/2003

Although several changes were highlighted in May, the specifics surrounding Dominic were particularly vague. The Google Bots, 'Freshbot' and 'Deepcrawler' searched the web and a significant number of websites reported bounces. Furthermore, the way in which backlinks were counted or reported appeared to change dramatically.
+Webmaster World

Cassandra - 15/04/2003

Google implemented a series of steps to address some basic issues with the quality of links including extensive linking from co-owned domains. Cassandra also heavily penalised sites for hidden text and links contained within web pages.

+Webmaster World

Boston - 15/02/2003

The first named Google Update which was announced at SES Boston. Initially, Google aimed to roll out major updates on a monthly basis. The first few updates combined a series of algorithm changes and large index refreshes (known as the 'Google Dance'). As the updates were rolled out more frequently, the monthly schedule of updating soon disappeared.

1st Documented Update - 15/09/2002

Before the introduction of the first named update 'Boston', there was a major shuffle which took place in the Autumn of 2002. Although the details are unclear, these changes appeared to be much more than the monthly PageRank and Google Dance updates. One webmaster said of Google: "they move the toilet mid stream".
+Webmaster World
+Level343

Google Toolbar PageRank (TBPR) - 15/12/2000

The browser toolbar was released by Google as well as its Toolbar Page Rank (TBPR). This was the start of many years of arguments in the SEO community. Soon after the TBPR was released, the Google Dance began.
+Google