[Spivak]

The thing I don't really understand is why not just opensource it at that point? Keep the rights to the source, but let customers audit, modify, and distribute those modifications to the community. Being able to audit the calculations your software is doing seems like it would bring a lot of confidence to engineers even if a small minority actually look, privacy and FOSS advocates would tolerate it, and they get bug reports and possibly a few free patches.

Businesses and professionals would still pay for valid licenses and enthusiasts get a 'community edition' to get them hooked. It seems like it's a win-win.