Yahoo, Microsoft Gain Search Share In May … Or Maybe Not

Both Yahoo (YHOO) and Microsoft (MSFT) gained ground in the U.S. search market in May, new data from ComScore shows – although the numbers for Yahoo and Microsoft continue to be distorted by the auto-generated searches created by slide shows on Yahoo News and other similar gimmicks.

Here’s whats the raw numbers show:

• Google‘s (GOOG) share of the market slipped to 63.7%, from 64.4% in April.
• Yahoo’s share improved to 18.3%, from 17.7%%
• Microsoft Bing’s share is now 12.1%, up from 11.8%.
• AOL’s (AOL) share is 2.3$%, down from 2.4%.

Broadpoint.Amtrech analyst Ben Schachter adjusts the numbers for both Yahoo and Microsoft’s use of of various search-distorting tricks; he asserts that on an adjusted basis, Yahoo lost about 30 basis points of market share in May to 16.6%, while Microsoft’s share was about flat at 10.8%, and Google gained 30 basis points to 66.4%.

Schachter writes that “unfortunately,” ComScore’s methodology will continue to impact the usefulness of its reported data. “It is easy to make adjustments for May (based on the numbers provided), but understanding the baseline of comScore’s “core” search will only become less clear,” he writes. “At the end of the day, YHOO can point to gaining share according to comScore, but investors will likely need to see the financial results before giving the company credit for any gains or stabilization.”