By Nick Kostov in Paris and Sarah E. Needleman in New York 

Ubisoft Entertainment SA's yearlong battle to stay out of Vincent Bolloré's clutches is coming to a head.

The maker of "Assassin's Creed" and other popular videogame series is slated to hold a shareholder meeting Thursday and has been bracing itself for Mr. Bolloré's Vivendi SA, with a 23% stake, to ask for board representation. That, analysts and Ubisoft executives say, could open the door to a more active role for Mr. Bolloré in the company, or even a full takeover.

A Vivendi spokesman declined to comment on whether Vivendi plans to seek board representation at Ubisoft's shareholder meeting. As of Tuesday, the company didn't plan to do so, people familiar with the matter said.

Still, the two sides have been quietly wooing shareholders in the standoff. Ubisoft, founded three decades ago by France's Guillemot family, last year enlisted advisory firm Lazard Inc. to help fend off any unsolicited approach. In February, it held a special shareholder meeting at which it took the unusual step of disclosing its financial targets for the next three years instead of one.

Vivendi, meanwhile, has been pushing for board representation since April and argues there are synergies to be found between Ubisoft and Vivendi's music, movie and television, and videogame units.

"We believe the voting outcome is likely to be extremely tight and therefore it is probable that every shareholder's vote will carry importance," said Robert Berg, an analyst at Joh. Berenberg, Gossler & Co., in a note to investors earlier this month.

Vivendi's stake-building in Ubisoft highlights the growing significance of the $100 billion videogame industry to the world's media companies. Once comprising simple arcade and home-computer titles popular with teens, videogaming has matured into a pastime integrated throughout popular culture, generating revenue for publishers in areas from movies to theme parks. It is also a rising professional sport, with mainstream advertisers sponsoring teams that compete in matches watched by millions of fans across arenas and the web.

Game companies with a record of producing hit franchises are "highly attractive" acquisition targets, said Benchmark Co. analyst Mike Hickey. He cited the June agreement of China's Tencent Holdings Ltd. and partners to buy a controlling stake in Supercell Oy, the Finnish creator of the mobile blockbuster "Clash of Clans," for $8.6 billion.

For Ubisoft, the threat of a hostile takeover is real. Mr. Bolloré, who as chairman of Vivendi calls the shots with just a 15% stake, has made a fortune over the past three decades often by using shareholder resolutions to seize control of businesses. He orchestrated Vivendi's hostile takeover in May of mobile-game developer Gameloft SE, another business founded by the Guillemot family.

"We made a bet straight away that Vivendi was not going to make an offer, " said a person familiar with Ubisoft's thinking. "We knew last year that we would have to win the [annual general meeting] and to do that we had to get shareholder support."

Ubisoft has stressed that losing control over decisions about partnerships and licensing deals tied to its intellectual property would hurt shareholders if the company were to become a part of Vivendi.

Vivendi has said that Ubisoft, with a market capitalization of EUR3.86 billion ($4.34 billion), would benefit from its industrial and financial backing to grow and better compete with larger U.S. rivals such as Activision Blizzard Inc. and Electronic Arts Inc.

Ubisoft's stock has risen 86% over the past 12 months, boosted in part by takeover speculation, while Vivendi's has dropped 15% as investors sought more details about the company's strategy.

"We won't relax until they sell their shares," Yves Guillemot, co-founder, chairman and chief executive of Ubisoft, said in an interview Friday from his office in Paris overlooking a graveyard. "The creeping control strategy implemented by Vivendi is dangerous. We think that there's a great risk of shareholders losing value."

Vivendi has experience in the videogame business. In 2007, under different management, it bought a 52% stake in Activision Blizzard for $18.9 billion. Six years later, though, Vivendi sold its stake in videogame maker, saying there was too little synergy with its music and pay-TV businesses. Activision's share price has nearly tripled since.

Today, Vivendi believes videogame assets are essential to its goal of becoming a European giant in media and content. Ubisoft "is part of a strategic vision of operational convergence between Vivendi's content and platform and Ubisoft's productions in the field of videogames," the media company said. On July 18, it said that it wasn't considering launching a full takeover bid for at least six months.

"Since we became a shareholder, we have written requesting meetings but so far nothing has happened," said a Vivendi spokesman. "We feel it would be normal as the main shareholder to have a seat on the board, but we're not in a hurry."

For its part, Ubisoft says Vivendi has refused to provide a written document about what a future with the two companies working together might look like, which Vivendi confirms. Mr. Guillemot said repeated requests for insight into Vivendi's strategy for the company have gone unanswered.

Write to Nick Kostov at Nick.Kostov@wsj.com and Sarah E. Needleman at sarah.needleman@wsj.com

(END) Dow Jones Newswires

September 28, 2016 02:48 ET (06:48 GMT)