Europe's largest media buyer, Aegis Group, continues to attract more attention from potential suitors. The company, which boasts Carat and Vizeum as two of its buying firms along with research branch Synovate, is said to have met with more than one possible bidder. Shares of Aegis Group were up 3.5% Tuesday on the London exchange on the latest news. They have risen more than 45% since July on rumors of a potential takeover bids. London's WPP Group ( WPPGY) is now said to be considering an offer in tandem with U.S. based equity player Hellman & Friedman. France's Publicis Groupe ( PUB) would also like to acquire the business and has held ongoing talks with company leadership. Meanwhile, Havas ( HAVS) Chairman Vincent Bollore has raised an 11% stake in Aegis since late summer, fueling speculation that the company was ripe for takeover. Corporate raider Bollore conducted a methodical takeover of Havas over the past year, putting the finishing touches on his campaign in July that saw widespread leadership change at the French ad holding company.