What does Fraunhaufer have to do with it? If we're randomly guessing which company might have instigated this investigation, I'd guess Sisvel, because it's easy

What does Fraunhaufer have to do with it? If we're randomly guessing which company might have instigated this investigation, I'd guess Sisvel, because it's easy to imagine for them to have an actual case: Sisvel has created an AV1 patent pool and iirc even made an open call for patent owners to approach them to get their patents added to the pool. It's easy to see how an anti-trust complaint could arise if someone left the pool or didn't join it because of real or imaginary pressure from AOMedia members.