Google Inc. and Yahoo Inc. both modestly expanded their share of the U.S. online search market in May, while Microsoft Corp.'s share of the market fell, according to estimates released by ComScore Inc. Thursday.
ComScore's May search report concluded that of a total of 10.78 billion searches conducted in the U.S. during the month, 61.8 percent of searches, or 6.66 billion, were conducted on Google sites, compared with 61.6 percent, or 6.51 billion, in April.
The report showed 20.6 percent of U.S. searches, or 2.22 billion, were conducted on Yahoo sites in May, compared with 20.4 percent, or 2.16 billion, in April.
ComScore reported Microsoft sites captured 8.5 percent of U.S. searches, or 920 million, in May, compared with 9.1 percent, or 961 million, in April.
Searches through Time Warner Inc.'s AOL LLC declined slightly to 4.5 percent of searches, or 486 million, from 4.6 percent, or 491 million, in April.
Searches through IAC/InterActiveCorp.'s Ask.com network rose a bit, as the network captured 4.5 percent of searches, or 486 million, compared with 4.3 percent, or 458 million, in April.
The search report is based on the five major search engines, taking into account partner searches and cross-channel searches. It excludes searches for mapping, local directory and user-generated video sites. While these measures are good as a gauge, they do rely heavily on online recruitment techniques dismissed by other more traditional pollsters. ComScore's data is closely watched by analysts and investors, but the company was criticized several months ago for a separate report on paid search clicks, which relies on a similar panel as the data on search market share.