Yes. In July 2012, the European Court of Justice has made a principle decision, declaring the trade with used software as inherently legal.
According to the grounds for the judgement, „the exhaustion doctrine is valid from the first sale of a software product“. The exhaustion pertains to every single licence, making the splitting of volume licences possible, as confirmed by the Federal Court of Justice of Germany (Federal Court of Justice of Germany, 12/11/2014, file no. I ZR 8/13).
The decision also applies to licences which have been transferred online. Buyers of used software are even entitled to download the software product again from the software vendor's site. The ECJ justifies this decision as follows: „Moreover, the exhaustion of distribution rights applies to the creator's or legal owner's programme copy, too in latest and improved form“ (ECJ 07/03/2012, file no. C-128/11).
On July 17, 2013, the Federal Court of Justice of Germany, implemented the decision by the ECJ on a national level. In Germany, it is legal to remarket used software licences and to transfer all rights of usage for the software to the subsequent purchaser. Physical and noncorporeal program copies are treated equally (Federal Court of Justice of Germany, 07/17/2013, file no. I ZR 129/08).
What about volume licences, in particular?
Even the sale of volume licences is legally unproblematic, since „the ECJ's decision also applies to volume licences and the process of splitting them into single licences.“ That was confirmed by the Higher Regional Court in Frankfurt in December 2012 in a lawsuit between Adobe and a used software dealer (Higher Regional Court Frankfurt on the Main, 12/18/2012, file no. 11 U 68/11). This decision was confirmed by the Federal Court of Justice of Germany in December 2014 (Federal Court of Justice of Germany, 12/11/2014, file no. I ZR 8/13).