Google Algorithm Change History
Unnamed Update — March 24, 2014
Major algorithm flux trackers and webmaster chatter spiked around 3/24-3/25, and some speculated that the new, "softer" Panda update had arrived. Many sites reported ranking changes, but this update was never confirmed by Google.
Page Layout #3 — February 6, 2014
Google "refreshed" their page layout algorithm, also known as "top heavy". Originally launched in January 2012, the page layout algorithm penalizes sites with too many ads above the fold.