Activist hedge fund Jana Partners is pushing theme park operator Six Flags Entertainment to consider a potential sale, according to sources familiar with the matter. The investor sent a letter to the company's board on Tuesday, demanding it immediately hire an investment bank to evaluate sale options, citing disappointment with Six Flags' second-quarter financial performance.

Last month, Six Flags reported its net loss widened to $202.6 million from $99.6 million in the same period a year earlier. As of Tuesday, the company's market capitalization stood at roughly $1.2 billion, with its share price falling approximately 42% over the past year.

The company has been working on a business turnaround amid declining attendance figures. It has already sold seven non-core parks to EPR Properties and shut down another park in Maryland after the end of the 2025 operating season.