OK, I stand corrected. However, it sounds like technically you must possess a copy of the binary to request source code, although the GPL doesn't require you to

OK, I stand corrected. However, it sounds like technically you must possess a copy of the binary to request source code, although the GPL doesn't require you to furnish proof that you have such a binary. IE there must be a chain of transferring the written offer from company to purchaser to third party. Or in other words you must have a copy of that written offer in order to request the source code (and the text of the FAQ seems to support that).