The EU Court of Justice ruled (judgement of 12 Oct 2016, case C-166/15) that the lawful acquirer of a copy of a computer program accompanied by an unlimited licence for the use of that program is not authorised to sell a back-up copy of that program. He can only sell the program on the original medium. Any sale of the back-up copy would require authorisation from the licensor.
01.02.2017