Tribune Publishing, the owner of the Los Angeles Times and the Chicago Tribune, said billionaire Patrick Soon-Shiong invested $70.5 million in the company, becoming its second largest shareholder.
The company also rejected on Monday Gannett's latest takeover offer, but said it would allow the publisher of USA Today access to some confidential corporate information.
Los Angeles-based Soon-Shiong, through his fund Nant Capital, will hold about 12.9 percent in Tribune and join the publisher's board as vice chairman on June 2.
Soon-Shiong, a South African-born surgeon, is part-owner of the Los Angeles Lakers basketball team. He founded two drug companies, which he sold for a total of $8.6 billion.
Nant Capital has also entered into a standstill agreement with Tribune, limiting its ability to raise stake in the publisher.
Reuters reported on Sunday that Tribune was planning to reject Gannett's offer, valued at $864 million including debt.
Tribune said on Monday that the $15 per share cash offer by Gannett was not in the best interests of shareholders. Gannett had raised its offer last week from $12.25 per share.
Oaktree Capital Management LP, a major shareholder of Tribune, urged the company to form an independent board to consider the proposal, according to a filing.
Oaktree owned about 4.7 million shares of Tribune, or 14.8 percent stake, as of May 20, according to Thomson Reuters data.