WB nearly doubles stake in Sci Ent.

Studio now able to buy up to 30% of stock

British videogame publisher Sci Entertainment has opened the door for Warner Bros. to nearly double its stake, while also giving its shares a much-needed boost.

Maker of “Tomb Raider” games, which is changing its corporate name to the consumer brand Eidos, has agreed to let the studio buy up to 30% of its stock.

WB initially bought a 10% stake in Sci in December 2006. It acquired more shares in April and earlier this month, with the total now at 16.1%.

Warner’s home entertainment group topper Kevin Tsujihara recently ankled Sci’s board, apparently due to conflict-of-interest concerns as the studio bought more shares.

WB is not committed to buy any more Sci stock and has no specific plans to do so.

However, Sci’s announcement that WB can up its stake to as much as 30% by Dec. 1 sent the company’s flagging stock up 11%. It closed Monday at 20 pence (31¢) per share.

Since Warner Bros. agreed to invest $30 million to buy more Sci shares in April, the publisher’s stock has plunged by 57%.

Warner Bros.’ growing stake in Sci has allowed it to secure a deal to distribute the publisher’s games in North America but hasn’t yet led to the takeover bid about which many have speculated.

Studio is soon expected to put a new exec on Sci’s board in Tsujihara’s place, most likely its recently appointed videogame unit prexy, Martin Tremblay.