You mean like when those guys making the JMRI model train software that had some jerk company take their code without respecting the OSS license, then patented something they'd been doing for years and counter-sued them for infringing that patent when they tried to get them to respect the license?

Yeah, I'd call that stolen (or at least 'attempted theft'), because they were about to lose their rights. Thankfully, the JMRI guys won in court, so they got their rights back.