[astonex]

Blizzard is not a separate company with just a publishing contract like Bungie did. Blizzard was bought out by Activision and is now Activision-Blizzard and treated as a subsidiary company.

I suppose Blizzard could try to raise enough capital to buy themselves but I think its unlikely

[SneakerXZ]

Blizzard was not bought. It was owned for more than decade by Vivendi, and it merged with Activision.