Google Algorithm Change History

We all very much aware of Google algorithm changes every year. While most of these changes are minor, every few months Google rolls out a “major” algorithmic update that affects search results in significant ways.

Below, I’ve listed the major algorithmic changes that made the biggest impacts on search. Am posting this to understand these updates can help with search engine optimization.

2012 Updates

Page Layout #2 — October 9, 2012

Google announced an update to its original page layout algorithm change back in January, which targeted pages with too many ads above the fold. It's unclear whether this was an algorithm change or a Panda-style data refresh.

Penguin #3 — October 5, 2012

After suggesting the next Penguin update would be major, Google released a minor Penguin data update, impacting "0.3% of queries". Penguin update numbering was rebooted, similar to Panda - this was the 3rd Penguin release.

August/September 65-Pack — October 4, 2012

Google published their monthly (bi-monthly?) list of search highlights. The 65 updates for August and September included 7-result SERPs, Knowledge Graph expansion, updates to how "page quality" is calculated, and changes to how local results are determined.

Exact-Match Domain (EMD) Update — September 27, 2012

Google announced a change in the way it was handling exact-match domains (EMDs). This led to large-scale devaluation, reducing the presence of EMDs in the MozCast data set by over 10%. Official word is that this change impacted 0.6% of queries (by volume).

Panda #20 — September 27, 2012

Overlapping the EMD update, a fairly major Panda update (algo + data) rolled out, officially affecting 2.4% of queries. As the 3.X series was getting odd, industry sources opted to start naming Panda updates in order (this was the 20th).

Panda 3.9.2 — September 18, 2012

Google rolled out another Panda refresh, which appears to have been data-only. Ranking flux was moderate but not on par with a large-scale algorithm update. 

Panda 3.9.1 — August 20, 2012

Google rolled out yet another Panda data update, but the impact seemed to be fairly small. Since the Panda 3.0 series ran out of numbers at 3.9, the new update was dubbed 3.9.1.

7-Result SERPs — August 14, 2012

Google made a significant change to the Top 10, limiting it to 7 results for many queries. Our research showed that this change rolled out over a couple of days, finally impacting about 18% of the keywords we tracked.

DMCA Penalty — August 10, 2012

Google announced that they would start penalizing sites with repeat copyright violations, probably via DMCA takedown requests. Timing was stated as "starting next week" (8/13?).

June/July 86-Pack — August 10, 2012

After a summer hiatus, the June and July Search Quality Highlights were rolled out in one mega-post. Major updates included Panda data and algorithm refreshes, an improved rank-ordering function (?), a ranking boost for "trusted sources", and changes to site clustering. 

Panda 3.9 — July 24, 2012

A month after Panda 3.8, Google rolled out a new Panda update. Rankings fluctuated for 5-6 days, although no single day was high enough to stand out. Google claimed ~1% of queries were impacted.

Link Warnings — July 19, 2012

In a repeat of March/April, Google sent out a large number of unnatural link warnings via Google Webmaster Tools. In a complete turn-around, they then announced that these new warnings may not actually represent a serious problem.

Panda 3.8 — June 25, 2012

Google rolled out another Panda data refresh, but this appeared to be data only (no algorithm changes) and had a much smaller impact than Panda 3.7.

Panda 3.7 — June 8, 2012

Google rolled out yet another Panda data update, claiming that less than 1% of queries were affect. Ranking fluctuation data suggested that the impact was substantially higher than previous Panda updates (3.5, 3.6).

May 39-Pack — June 7, 2012

Google released their monthly Search Highlights, with 39 updates in May. Major changes included Penguin improvements, better link-scheme detection, changes to title/snippet rewriting, and updates to Google News.

Penguin 1.1 — May 25, 2012

Google rolled out its first targeted data update after the "Penguin" algorithm update. This confirmed that Penguin data was being processed outside of the main search index, much like Panda data.

Knowledge Graph — May 16, 2012

In a major step toward semantic search, Google started rolling out "Knowledge Graph", a SERP-integrated display providing supplemental object about certain people, places, and things. Expect to see "knowledge panels" appear on more and more SERPs over time. Also, Danny Sullivan's favorite Trek is ST:Voyager?!

April 52-Pack — May 4, 2012

Google published details of 52 updates in April, including changes that were tied to the "Penguin" update. Other highlights included a 15% larger "base" index, improved pagination handling, and a number of updates to sitelinks.

Panda 3.6 — April 27, 2012

Barely a week after Panda 3.5, Google rolled out yet another Panda data update. The implications of this update were unclear, and it seemed that the impact was relatively small.

Penguin — April 24, 2012

After weeks of speculation about an "Over-optimization penalty", Google finally rolled out the "Webspam Update", which was soon after dubbed "Penguin." Penguin adjusted a number of spam factors, including keyword stuffing, and impacted an estimated 3.1% of English queries.

Panda 3.5 — April 19, 2012

In the middle of a busy week for the algorthim, Google quietly rolled out a Panda data update. A mix of changes made the impact difficult to measure, but this appears to have been a fairly routine update with minimal impact.

Parked Domain Bug — April 16, 2012

After a number of webmasters reported ranking shuffles, Google confirmed that a data error had caused some domains to be mistakenly treated as parked domains (and thereby devalued). This was not an intentional algorithm change.

March 50-Pack — April 3, 2012

Google posted another batch of update highlights, covering 50 changes in March. These included confirmation of Panda 3.4, changes to anchor-text "scoring", updates to image search, and changes to how queries with local intent are interpreted.

Panda 3.4 — March 23, 2012

Google announced another Panda update, this time via Twitter as the update was rolling out. Their public statements estimated that Panda 3.4 impacted about 1.6% of search results.

Search Quality Video — March 12, 2012

This wasn't an algorithm update, but Google published a rare peek into a search quality meeting. For anyone interested in the algorithm, the video provides a lot of context to both Google's process and their priorities. It's also a chance to see Amit Singhal in action.

Panda 3.3 — February 27, 2012

Google rolled out another post-"flux" Panda update, which appeared to be relatively minor. This came just 3 days after the 1-year anniversary of Panda, an unprecedented lifespan for a named update.

February 40-Pack (2) — February 27, 2012

Google published a second set of "search quality highlights" at the end of the month, claiming more than 40 changes in February. Notable changes included multiple image-search updates, multiple freshness updates (including phasing out 2 old bits of the algorithm), and a Panda update.

Venice — February 27, 2012

As part of their monthly update, Google mentioned code-name "Venice". This local update appeared to more aggressively localize organic results and more tightly integrate local search data. The exact roll-out date was unclear.

February 17-Pack — February 3, 2012

Google released another round of "search quality highlights" (17 in all). Many related to speed, freshness, and spell-checking, but one major announcement was tighter integration of Panda into the main search index.

Ads Above The Fold — January 19, 2012

Google updated their page layout algorithms to devalue sites with too much ad-space above the "fold". It was previously suspected that a similar factor was in play in Panda. The update had no official name, although it was referenced as "Top Heavy" by some SEOs.

Panda 3.2 — January 18, 2012

Google confirmed a Panda data update, although suggested that the algorithm hadn't changed. It was unclear how this fit into the "Panda Flux" scheme of more frequent data updates.

Search + Your World — January 10, 2012

Google announced a radical shift in personalization - aggressively pushing Google+ social data and user profiles into SERPs. Google also added a new, prominent toggle button to shut off personalization.

January 30-Pack — January 5, 2012

Google announced 30 changes over the previous month, including image search landing-page quality detection, more relevant site-links, more rich snippets, and related-query improvements. The line between an "algo update" and a "feature" got a bit more blurred.

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