SPORTINGBET is to back an increased takeover offer from Britain’s biggest bookmaker William Hill in a deal valuing the online firm at more than £400m.

The company, which offers sports betting and casino games and owns Paradise Poker, said it would unanimously recommend a 61.1p per share proposal to its shareholders.

William Hill, in a joint proposal with European gaming company GVC, previously offered 52.5p a share, which valued Sportingbet at around £350m.

But Sportingbet, founded in 1997 and with 700,000 active customers in markets across 26 countries, rejected the initial approach.

The firm – previously a bid target for bookmaker Ladbrokes – said the first proposal undervalued the company and its prospects.

The current deal, which including other assets such as bonds, values Sportingbet at closer to £530m, and is now subject to various terms and conditions and shareholder approval.

William Hill and GVC have until November 13 to make a firm offer.

Guernsey-based Sportingbet was set up by now venture capital investor Mark Blandford, who floated the firm in 2001 and left day-to-day operations in 2006.

The company is now the largest online sports betting provider in several countries such as Australia, Spain, and Greece.