Quite. There's what used to be an easy test for whether you were bound by a contract: did you make an agreement with someone, someone's agent, or a corporation

Quite. There's what used to be an easy test for whether you were bound by a contract: did you make an agreement with someone, someone's agent, or a corporation's employee? In the age of EULA's, that test isn't as clear as it was, but it is perfectly clear that you can come into possession of copyrighted material without any kind of contract. Copyright limits what you can do with your possessions without your explicit or tacit agreement. Licenses can only grant freedoms. The GPL-style licenses seem to inhibit your freedom, but only because they offer a conditional freedom: you are granted the freedom to do this thing, but only if you also undertake to do that thing. All of this is without any agreement between the code author and the code user. Now here's a test of whether that is all clear: is an End User License Agreement a license?