13. I have bought a lawful copy of a CD containing a computer program. Do I infringe copyright by reselling the CD through an auction on the Internet?
No. Reselling a computer program by itself does not infringe copyright, provided that you have fully uninstalled the program and deleted all copies of it from your computer before you complete the resale.
However, you must check the terms of the user licence for the computer program before you resell the program. If the user licence expressly prohibits resale of the program (e.g. by expressly disallowing the transfer of the user licence, or the user licence will be automatically terminated upon a transfer), then your resale of the program may not transfer a valid user licence to the subsequent purchaser. This in effect renders the resale of the program ineffective (see section 64 of the Copyright Ordinance).