We all remember movie theaters, yes? Building with large, dark rooms where we gathered to watch films together, back when such groupings weren't inadvisable? At the point where theaters were a going concern, superhero movies were the dominant storytelling form of the decade, and that success begat more and more franchises, folding in secondary and tertiary characters from the canon. That expansion not only tested audiences' appetite for super-powered fare but eventually the limits of branding.
Marvel faces such a test as it prepares the small-screen superhero show WandaVision for Disney+ audiences as some indeterminate point in the future. While the movie-going public may have acquiesced to Marvel's desires, a Hong Kong-based company is pushing back against Marvel's trademark bids surrounding the show's branding.
According to CinemaBlend, The Wanda Group Ltd is contesting Marvel's trademark applications for varied potential products based upon the WandVision series. The Wanda Group has a list of product trademarks that would make Disney proud, per the article, including toys, games and sports equipment, all of which would seem to be ripe for merchandising for any Marvel property (although Wanda Maximoff, nee Scarlet Witch, and The Vision would probably be less in demand than, say, Captain America.)
Nevertheless, it's a complication for a company that has spent the past ten-plus years garnering success after success, with the occasional misstep (Thor: The Dark World springs to mind.) It seems unlikely that the show will make significant changes for the sake of a trademark battle; regardless of who holds the rights to a mark, it's hard to imagine how any confusion would not ultimately redound to the benefit of the Marvel property over all else. When someone mentions "Iron Man," I think of Robert Downey Jr. in CGI armor, not a Black Sabbath song from the 1970s; similarly, Black Panther evokes Wakanda, not the political group of the 1960s.
In that regard, it's worth thinking about trademarks in the context of a monoculture. Intellectual property law is nothing in the face of broad public consciousness, and Marvel can reach more people than any company contesting its claims ever could. And the same could be said of any company that might have a legitimate claim but nowhere near the sway of a company with blockbuster films that tens of millions of people watch. It's a relatively new problem that has accompanied the internet, and one that other businesses may run into before too long.