Google increased its share of the US internet search engine market in October, taking share away from rivals Yahoo and Microsoft, according to market researcher ComScore.

Google widened its lead over the competition by winning 58.5 per cent of all US searches last month, up 1.5 percentage points over September. Yahoo took second place with 22.9 per cent of the search market, down from 23.7 per cent, while third ranked Microsoft dropped to 9.7 per cent from 10.3 per cent.

Ask Network remained steady at fourth place with 4.7 per cent of the search market in October, while the Time Warner Network dropped a tad to 4.2 per cent from 4.3 per cent a month earlier, ComScore reported.

Google captured 6.1 billion of the 10.5 billion internet searches Americans conducted in October, ComScore said, far more than second place Yahoo's 2.4 billion.