Microsoft is not going to let a cash cow revenue producing app like office or word stop selling. They will pay off this other company, or buy the whole company, as they have done things like that in the past.
If company isn't public, it is impossible to buy it. It's a private property. And if I was an owner, by seeing these figures already (300M fined)... I would play poker with MS. They can be really in trouble.
Saving docx format can be worth 1 B$, who knows...
