Tribune Publishing, the Chicago-based parent of The Baltimore Sun and several other major newspapers, on Wednesday rejected an $815 million acquisition bid by McLean-based Gannett, the publisher of USA Today according to a post by Potomac Tech Wire. “While the board is always open to evaluating any credible proposal that it believes to be in the best interests of the company and its shareholders, Gannett’s opportunistic proposal understates the company’s true value and is not a basis for further discussion,” wrote Tribune CEO Justin Dearborn in a letter to Gannett Chairman John Jeffry Louis and President and CEO Robert Dickey. Gannett, which currently owns 107 daily newspapers in 34 states and Guam, last month offered to pay $12.25 a share in cash and assume about $390 million of Tribune’s outstanding debt in a deal that would unite two of the nation’s three largest newspaper publishers. Louis responded to Tribune’s rejection by saying its announcement “reaffirms our concern from the outset that Tribune’s board never intended to engage with us.” He also said that Gannett has launched a proxy campaign to solicit “withhold” votes in connection with the election of all eight nominees to Tribune’s board. “This campaign will allow all Tribune stockholders the opportunity to send a clear message to Tribune’s board that it should substantively engage with Gannett regarding its proposal,” wrote Louis.