15541 posts since 10 Apr, 2010, from Germany
Or maybe the OP should have read the resale policy, before attempting to sell the respective plugins. You wouldn't believe how many times i read about people trying to sell Propellerhead rack extensions, for example, and people neither had any idea that they're not supposed to resell those, nor how the actual transfer is working. Because it won't work at all, unless you sell your whole account, and the person buying it changes all its details. And probably locks himself out of any support option in the process. At least that wouldn't surprise me at all.
It'd be really grand if people read more EULA's, and familiarize themselves with the terms they accept when buying, installing and using the software. It's really important, and you have that responsibility as a buyer. For yourself, most importantly.