But owning SeaWorld became a liability to its reputation after “Blackfish” debuted at the 2013 Sundance Film Festival. The film, which was eventually picked up by CNN, offered an indictment of SeaWorld’s care of Tilikum, an orca that became one of the park’s biggest stars, but that also was involved in the deaths of three people, including his trainer.

Outrage over the film metastasized quickly into calls to prohibit keeping killer whales in captivity. Firms like Southwest Airlines severed ties to SeaWorld. The controversy eventually depressed attendance at SeaWorld’s theme parks, leading to the ouster of its chief executive in 2015.

Since then, SeaWorld has stopped breeding whales and announced plans to phase out its famous orca shows in favor of attractions without live animals.

Nevertheless, SeaWorld proved a winner for Blackstone financially. The firm’s final return amounted to about $1.7 billion, or 2.7 times its original investment, according to a person briefed on the matter, who was not authorized to speak publicly. That figure includes all of the stock Blackstone sold and the dividends it collected from the company.

SeaWorld said that Blackstone sold its remaining 19.5 million shares to Zhonghong at $23 each, or 26 percent more than the closing price Thursday.