Microsoft Corp's Bing search engine continued to make small gains on rivals Google Inc and Yahoo Inc in the US Internet search market in July, according to the latest data from research firm ComScore.

Microsoft, which launched Bing in early June, racked up 8.9 percent of US Internet searches in July, up 0.5 percentage points from June. Google, the leader in the market, and Yahoo, the distant No. 2, both lost 0.3 percentage points of market share in July, to 64.7 percent and 19.3 percent, respectively.

Late last month Microsoft and Yahoo finally signed an agreement to cooperate on Internet search advertising, with Bing powering searches on both companies' sites and Yahoo handling the ad sales. The deal has yet to be approved by regulators and likely won't take full effect in the market until early 2012.