That's only because large corporations have so much existential inertia - it takes a long while to build a corporation up, and they tend to sink slowly enough t

That's only because large corporations have so much existential inertia - it takes a long while to build a corporation up, and they tend to sink slowly enough that they leave evidence of where their IP goes. That said, it's not too hard for corporate IP to become orphaned. A company makes a bad investment, gets bought out by another company that gets bought out by a third, and records get lost.