The company that owns the Philadelphia Inquirer newspaper has said it is interested in mounting a rival bid for the Dow Jones media group.
Dow Jones owns the Wall Street journal
Philadelphia Media Holdings chief executive Brian Tierney indicated that his firm would be willing to offer as much as Rupert Murdoch's current bid.
Mr Murdoch's News Corporation made its $5bn (£2.5bn) offer for the Wall Street Journal owner at the start of May.
While Dow Jones has yet to decide on this bid, its unions are opposed.
"We don't believe News Corporation is overpaying," said Mr Tierney.
"This is one of the greatest journalistic enterprises ever created."
His comments came as the main union at Dow Jones said an unnamed internet entrepreneur and Wall Street group were also looking at mounting a possible bid.
The union, the Independent Association of Publishers' Employees, has also approached billionaire investors Ron Burkle and Warren Buffett.
'Editorial independence fears'
Dow Jones' future is in the hands of the Bancroft family, which controls 64% of the firm's voting rights.
Mr Murdoch held his first meeting with members of this family earlier this week and both sides said the talks were "constructive".
Yet neither gave any more details, especially regarding whether the family was willing to sell.
Amid fears that Mr Murdoch will interfere in the running of the Wall Street Journal, he has already promised to establish "an independent, autonomous editorial board" for the newspaper if his bid for Dow Jones is accepted.
The main US share index is named after the Dow Jones company.