Need a law - implanted medical devices require lifetime support / Open source and release all proprietary source code if the company goes bankrupt.

This is a very compelling argument for government ownership of a controlling interest in all biotechnology. Your device will be perpetually supported--at taxpayer expense if necessary. That a device could no longer receive improvement can be allowed to be a possibility, but that it could become a novel medical hazard is something that should be prevented at all reasonable cost.

The only way to ensure that this kind of innovation remains documented, and a person is always available who is paid to maintain expertise on it, is to back it with the government. That comes with its own set of problems, but a medical implant is not a pill you can stop taking or a prosthesis you can disconnect. It's with you forever, and in the future it will necessarily be prohibitive or outright impossible to remove. These advances in technology have to be accompanied with advances in polity.