From GameWatcher: “If you’re a fan of comic book video games, then you’re painfully aware of the fact that IP rights are a tricky thing to handle, what with various different titles getting taken off Steam and other marketplaces simply due to various contractual obligations and their subsequent dismissal. The latest case of license expiration may well be happening with the Marvel: Ultimate Alliance games.”
Source: N4G PC Marvel: Ultimate Alliance Games May Be Getting Delisted Soon