Google and Yahoo both gained search market share in October at the expense of Microsoft and Time Warner, according to a report released Monday by Internet metrics company comScore.

Google sites processed 45.4% of U.S. search queries, a gain of 0.3 percentage points from September. Yahoo handled 28.2% of searches during the same period, up 0.1 percentage points from the previous month.

At the same time, Microsoft's search market share dropped by 0.2 percentage points to 11.7% while Time Warner's search share declined by the same fraction, leaving it with 5.4% of the query market. Ask's share of U.S. searches remains steady at 5.8%.

Over the course of a year, Google has been showing steady growth, while Microsoft, Time Warner, and Yahoo all declined. Since October 2005, Google's share of the U.S. search market has risen by 6.4 percentage points, climbing steadily from 39% to 45.4%. Microsoft's and Yahoo's share of the market fell during this period by 2.9 and 1 percentage points respectively.

For the Time Warner Network, historic data provided by comScore begins with a figure of 5.6% for June, 2006. Four months later, that number sits at 5.4%.

Americans performed 6.8 billion searches in October, up 3% from September and 33% from a year ago.