I know a guy who got sued by his previous employer because he made something open-source he had been working on free time and had been kind enough to use that i

I know a guy who got sued by his previous employer because he made something open-source he had been working on free time and had been kind enough to use that in for the company as well. Because they want their name attached to it, and don't want its copyright held by him. I could be wrong but it's double standards unless something like this applies other way around as well. I should be able to sue and bring down a company I don't want using my code under shitty licenses by using say GPL, so that they have to make their own code OSS as well if they use my work. I want to be able to sue them to the ground, if they can sue me and my friends to the ground on a bullshit whim.