I dont worry about it. Marvel has Disney money and lawyers, and could get them back if they wanted to write a big enough check.
That and it allows some other properties to shine. Don't care about the Xmen or FF in MCU. Just want a couple side pieces like Doom, Galactus, Surfer and the heralds, Annihilus, Badoon, and Shiar be integrated in the MCU. In other words, give me some cosmic Marvel sci-fi. Fox isn't going to do shit with that aspect with their focus on earth.