The rights will become exercisable after a group buys more than 20 percent of Tribune Publishing's shares.
Gannett, the owner of USA Today, made a takeover bid for Tribune last month at $12.25 per share in cash, valuing the publisher of the Chicago Tribune and the Los Angeles Times at about $815 million. Tribune rejected the offer last week.
Tribune has been urged by Oaktree Capital, its second largest shareholder, to negotiate with Gannett about a possible takeover.
— CNBC contributed to this report.