Hachette, the French media giant that publishes Elle and Woman's Day magazines, said Thursday that media rival Havas was snapping up its shares.
The talk that one company was taking aim at another, still viewed as ungentlemanly in France, sent Hachette's stock soaring 12% on the Paris stock exchange.
"There is no doubt Havas is buying up" Hachette shares, a Hachette spokesman said. "I would note that Havas has not denied (this)."
Havas declined to comment.
Hachette, a leading publisher of books and periodicals, is best known for its stable of magazines, including Elle, Woman's Day and Popular Photography.
The company reported a $386-million loss last year because of its ill-fated foray into television. Its La Cinq French commercial television channel went off the air in April after racking up huge losses.
Havas, regarded as one of France's best-run companies, has a range of businesses that include advertising, pay television, book publishing and tourism. It reported a $216-million profit last year.
Hachette shares closed up $3.36 to $31.74 on trade of 626,600 shares, nearly 3.2% of its outstanding stock.
Havas has made acquisitions in recent years, and this spring said it is still on the prowl.
At the end of 1991, Havas had net cash of $388 million, a sum that by July 30 had been boosted by $352 million after the exercise of equity warrants issued in 1989.
Media analysts said if Havas was building a stake, it might be seeking to make Hachette sell off its book publishing business, which would dovetail Havas' own.
"Hachette has wonderful brand names. There would be a lot of synergies between Havas' existing book business and Hachette's book publishing," said Rebecca Winnington-Ingram of Morgan Stanley International Inc.
A total of 615,800 Hachette shares, representing 3.1% of the group's outstanding stock, changed hands on Tuesday and Wednesday.
Analysts said any effort by Havas to build up a position in Hachette may be difficult because the rival is tightly in the grip of its chairman, Jean-Luc Lagardere.
"As long as our shareholders are with us, Havas can't do a thing," the Hachette spokesman said.
Lagardere, who plans to merge Hachette with its sister defense company, Matra, controls Hachette through a string of holding firms.
If Havas were to offer Hachette shareholders a better deal than Lagardere gives them through the planned merger with Matra, it might derail the deal.