Google's Google Panda is a major change to the company's search results ranking algorithm that was first released in February 2011. The change aimed to lower the rank of "low-quality sites" or "thin sites",^[1] in particular "content farms",^[2] and return higher-quality sites near the top of the search results.

CNET reported a surge in the rankings of news websites and social networking sites, and a drop in rankings for sites containing large amounts of advertising.^[3] This change reportedly affected the rankings of almost 12 percent of all search results.^[4] Soon after the Panda rollout, many websites, including Google's webmaster forum, became filled with complaints of scrapers/copyright infringers getting better rankings than sites with original content. At one point, Google publicly asked for data points to help detect scrapers better.^[5] In 2016, Matt Cutts, Google's head of webspam at the time of the Panda update, commented that "with Panda, Google took a big enough revenue hit via some partners that Google actually needed to disclose Panda as a material impact on an earnings call. But I believe it was the right decision to launch Panda, both for the long-term trust of our users and for a better ecosystem for publishers."^[2]

Google's Panda received several updates after the original rollout in February 2011, and their effect went global in April 2011. To help affected publishers, Google provided an advisory on its blog,^[6] thus giving some direction for self-evaluation of a website's quality. Google has provided a list of 23 bullet points on its blog answering the question of "What counts as a high-quality site?" that is supposed to help webmasters "step into Google's mindset".^[7] It has been incorporated in Google's core algorithm since 2015.^[8]

The name "Panda" comes from Google engineer Navneet Panda, who developed the technology that made it possible for Google to create and implement the algorithm.^[9][4]

Ranking factors

The Google Panda patent (patent 8,682,892), filed on September 28, 2012, was granted on March 25, 2014. The patent states that Google Panda creates a ratio with a site's inbound links, and reference queries, search queries for the site's brand. That ratio is then used to create a sitewide modification factor. The sitewide modification factor is then used to create a modification factor for a page based upon a search query. If the page fails to meet a certain threshold, the modification factor is applied and, therefore, the page would rank lower in the search engine results page.^[10]

Google Panda affected the ranking of an entire site or a specific section, rather than just the individual pages on a site.^[11]

Updates

For the first two years, Google Panda's updates were rolled out about once a month, but Google stated in March 2013 that future updates would be integrated into the algorithm and would therefore be continuous and less noticeable.^[12][13]

Google released a "slow rollout" of Panda 4.2 starting on July 18, 2015.^[14]