STX Entertainment

In 2012, Simonds and McGlashan began conceptualizing a media company based on the idea of producing medium-budget star-driven projects, a method that had fallen out of favor with Hollywood studios. The conversation led to the launch of STX Entertainment in 2014 (the "S" standing for Simonds, the company's founder; the "T" standing for TPG Growth, whose managing partner McGlashan helped launch the company; and the "X" standing for "secret project"), with the mission to finance, develop, produce, market, and distribute star-driven content around the world. Investors in the company included Hony Capital, Tencent, PCCW, TPG Growth, RTL Group, and Liberty Global. Individual investors included Gigi Pritzker, Beau Wrigley, and Dominic Ng.

In September 2017, it was reported that STX was considering an initial public offering (IPO) on the Hong Kong Stock Exchange (SEHK). It was reported that a listing on the SEHK could bring STX closer to Chinese investors and audiences. The Wall Street Journal stated that the company could be valued at $3.5 billion, after raising an additional $500 million following the IPO. In April 2018, the company filed for an IPO on the Hong Kong Stock Exchange.

STX called off its IPO in October 2018, citing the China–U.S. trade war, and conditions having deteriorated in Hong Kong due to turbulence in the mainland Chinese equity market. An overall co-funding agreement with the Chinese company Huayi Brothers Media lapsed at the end of 2018, and, in April 2019, co-founder Bill McGlashan was fired due to his being indicted in the college admissions bribery scandal.

In April 2020, STX announced that it would merge with the Indian film and television studio Eros International plc. Simonds stated that the merger would create "the first independent media company with the expertise and creative cultures of Hollywood and Bollywood, while also leveraging the important inroads both companies have made into the Chinese market." The combined company would be publicly traded, inheriting Eros' listing on the New York Stock Exchange. The merger was closed on July 30, 2020; the combined company unveiled a new logo and branding as ErosSTX in September. The combined entity raised $125 million of new equity funding and, led by JPMorgan, received $350 million in credit.

In December 2021, amid financial shortcomings following the merger, Jahm Najafi's Najafi Companies announced that it had reached an agreement to acquire STX Entertainment from ErosSTX for $173 million. However, in late January 2022, Lionsgate also emerged as a potential suitor, looking to absorb either part or all of STX; but that deal was later rejected, leaving only Najafi as a potential suitor. In April 2022, Najafi Companies completed its acquisition of STX Entertainment. Eros Media World would retain a 15% non-voting stake in the company. In July 2022, shortly after STX's motion picture chairman Adam Fogelson left the studio, Deadline reported that STX was in talks with Lionsgate over a potential film distribution deal. Shortly after, it was reported that STX Entertainment's U.K. offices, including the London office housing STXinternational's headquarters, were gradually shutting down. Following the departure of STXinternational head John Friedberg to join Black Bear Pictures's international division, it was announced that the latter company was nearing a deal with STX to handle part of its slate internationally. In November 2022, It was reported that STX's distribution and marketing operations would be shuttered and that Operation Fortune: Ruse de Guerre would go to a streaming service domestically, alternatives being considered for The Marsh King's Daughter, Lionsgate possibly taking over distribution for Ferrari, and with Greenland 2: Migration being packaged to other distributors. By February 2023, it was reported that Lionsgate had already taken domestic rights from Operation Fortune: Ruse de Guerre with plans to release it theatrically on March 3, 2023. In July 2023, Neon bought the distribution rights for Ferrari, with Neon releasing it on December 25, 2023.

In January 2026, Najafi sold STX Entertainment to Crown Productions, a subsidiary of insurance platform A-CAP, with Peter Coleman installed as its new CEO and Simonds and Fogelson leaving the company. STX will resume domestic distribution operations, with a target of producing films with budgets of up to $20 million.