The government could claim "ownership" over something all it wants, but unless it knows how (or cares enough) to crack it, such claims are pure bunk. Someone who automates and encrypts the key pieces of infrastructure in the enterprise, would make it impossible for the government to interfere. They could pull the plug on the service entirely. They could go after the enterprise's suppliers and compel them to turn over data/money (assuming those suppliers aren't themselves machine-run). But they won't be able to interfere with the machine's operation in any significant way without lobotomising it. And if we're talking about something sufficiently popular, any such moves by the government would become political suicide.

Legal claims are only ever as strong as your ability to enforce it. I can envision machine-run enterprises that are so well automated and encrypted, that any efforts by the government to interfere, would work about as well as governments trying to outlaw the common cold.