Spider-Man: Homecoming's worldwide box-office dominance is missing one major piece of the global puzzle: China.

So far in 2017, most major Hollywood tentpoles have opened in China day-and-date with North America, or just shortly after their U.S. debut. But sources in Beijing say Sony's Spider-Man: Homecoming has yet to be given an official release date, which means it is unlikely to open in the world's second-largest film market until at least August.

The same goes for 20th Century Fox’s War for The Planet of the Apes, opening in North America on Friday, and Luc Besson's Valerian, set for a North American debut on July 21. Christopher Nolan's Dunkirk, meanwhile, isn't expected to open in China until early September, well after its July 19 U.S. bow. 

The delays could cost Hollywood millions. In an increasingly integrated — and still piracy-vulnerable — global entertainment landscape, late release dates have been known to erode box office significantly.

The uncertainty surrounding these much-anticipated tentpoles is the clearest indication yet that Beijing's media regulators intend to reinstate their infamous blackout on foreign film imports during the lucrative summer moviegoing season.

Facing a slowdown in box-office growth, regulators cut the blackout season short in 2016, allowing a handful of U.S. studio titles into the market in late July and August. Some had speculated that China might abolish the summer blackout practice altogether this year, since Washington and Beijing trade officials are currently engaged in a high-stakes renegotiation of the U.S. film industry's terms of doing business in China. Allergic to the notion of American pop culture dominance, Beijing employs various means — including quotas, reduced revenue shares and blackouts — to limit Hollywood's access to the massive mainland Chinese theatrical market. The United States Trade Representative office, with the MPPA's urging, is understood to be pushing hard for China to give up such practices.

For their part, China's movie regulators — specially, the Film Bureau, within the State Administration of Press, Publication, Radio, Film and Television — find themselves trapped between competing priorities. Upper levels of the Chinese government are understood to demand that Chinese movies maintain at least a 55 percent market share at the national box office. At the same time, they want to see steady overall growth in the marketplace, so that China can overtake North America as the world's largest theatrical market as soon as possible (Pricewaterhouse Coopers currently forecasts China will claim that crown in 2020).

Box-office growth remained sluggish in the first half of the year, however, with total revenue climbing just 3.7 percent. And it was Hollywood that saved the Chinese market from an embarrassing loss. With local Chinese movies continuing to underperform, regulators allowed in a record 57 foreign films during the period — 14 more than last year. As a result, Chinese movies' market share plunged to just 39 percent. To get that number back above 55 percent — while also escaping a full-year decline and intense global trade heat from U.S. officials — the Film Bureau will have to execute some regulatory maneuvering that is nothing less than heroic.