If a customer purchases software from a reseller, and the software does not have a license agreement included with the purchase, is that customer a customer of the reseller or the company that owns the rights to the software?
The general rule is that a buyer cannot lawfully acquire more rights than the seller has to sell. So, if a software manufacturer sells a license to Person A that permits that person to use a piece of software but which prohibits its resale then Person B does NOT acquire good title to that software if he buys it from Person A. The software manufacturer can seek to recover that software from Person B or sue him for infringement.
The above response is general information ONLY and is not legal advice, does not form an attorney-client relationship, and should NOT be relied upon to take or refrain from taking any action. I am not your attorney. You should seek the advice of competent counsel before taking any action related to your inquiry.