I think this analogy depends entirely on communication and your ability to defend what you think of as your property. Applying the reverse logic, is it theft if

I think this analogy depends entirely on communication and your ability to defend what you think of as your property. Applying the reverse logic, is it theft if the person uses that software that you sold them access to? As far as I'm concerned, someone's property is what they can defend as their property. If someone has access to a license that you didn't intend to sell them, but also doesn't impair your ability to use it, then you now both have that property. Otherwise, if you clearly communicate that it's part of the deal, but then keep a backdoor in, and remove the software from the person's new computer, that's theft. The only way I'd argue that the software would remain yours after the transaction and when you forgot to exclude it, is if you maintained access to it somehow. Whether the person keeps it or not is up to their goodwill or ability to use the licenses. In the old days, if a computer came with a Photoshop license on it, it's yours.