Reuters reported that Danone shares jumped nearly 5%, in mid-September as some investors interpreted comments by French Industry Minister Francois Loos as a sign that France was dropping its efforts to shield the maker of Evian mineral water and Dannon yogurts from a hostile bid.

Groupe Danone chief executive Franck Riboud called the most recent rumors, "completely untrue" in a statement on Danone's website. "There have been no talks with PepsiCo and there are none now," the statement read.

Danone shares had gained as much as 27% in July on speculation PepsiCo could bid for it. After PepsiCo said it had not talked to Danone and was not pursuing a takeover, investor advocacy groups asked for an investigation into the possibility that insiders were trying to manipulate the market.