The Financial Times issued a brief apology for a blog post that said Paris-based Publicis Groupe planned to make a bid for U.S.-based rival Interpublic.

“Apologies, but our usually knowledgeable sources turned out to be lacking on this occasion,” FT said in an update to the post, which it has not removed from its site.

The update came after Publicis issued a statement refuting the details of the post.

“Publicis Groupe denies having engaged in any discussions with Interpublic Group of Companies and confirms that it has not commissioned any bank to undertake any such discussions,” according to the statement.

Adweek pointed out that shares of Interpublic were traded six-times higher than usual on Friday after the FT report went live.