Tribune Publishing shares are down 1.7% in early trading today after the owner of the Los Angeles Times reported that its board has adopted a so-called poison pill defense that could stop Gannett’s $400 million (not including debt) takeover effort.

“Based on Gannett’s approach and continued hostility, the Board is taking prudent measures to protect our shareholders’ best interests,” Tribune CEO Justin Dearborn says. “Our Board is unanimous that Gannett will not succeed with its current tactics and low-ball price. Tribune stakeholders deserve better and we are confident that the steps we are taking will create better opportunities for future value than engaging with Gannett under the current circumstances.”

The poison pill would kick in if someone buys 20% or more of Tribune’s stock. It would give all other investors the right to double their share of the company’s equity. The plan will only last a year, the company says, although there’s nothing that would prevent it from being renewed.

Gannett says that Tribune “is putting up another roadblock to prevent its stockholders from realizing compelling, immediate and certain cash value for their investment. The decision to implement a poison pill is yet another demonstration that Tribune’s Board and management team are not listening to its stockholders.”

The owner of USA Today has offered $12.25 a share for Tribune. That’s a nearly 63% premium to Tribune’s trading price before Gannett publicly announced its proposal.

Gannett is encouraging Tribune shareholders to register their support for a deal by withholding their votes for company directors at the June 2 annual meeting.

On Friday Tribune’s No. 2 shareholder, Oaktree Capital, said in an SEC filing that it would be “in the best interests of the [company] and its stockholders for [Tribune] to pursue discussions with Gannett to see if an acceptable agreement can be reached for Gannett to acquire [Tribune].”

But Tribune says it has a growth plan would be superior to Gannett’s offer.

A major expansion of the L.A. Times and a company-wide shift to digital publishing would help “more than offset revenue pressure in the traditional publishing business,” Tribune says. It has “a clear vision … innovative technologies as well as the experience necessary to execute that strategy.”

The company also says Gannett is taking advantage of a dip in Tribune’s stock due to “the elimination of the dividend and disclosure of a material accounting weakness.”