[sprout]

The VSL Terms of License states in section 2.

d) transfer the Software to another party if the other party agrees to accept all terms and conditions of this Agreement. If you transfer the Software to another party, you must at the same time transfer all copies, whether in printed or machine-readable form, to the same party and destroy any copies not transferred.
http://www.vsl.co.at/en/65/75/443/522/340.vsl

Furthermore see http://community.vsl.co.at/forums/p/30383/194797.aspx

I have a lot of the VSL libraries but I am interested in buying more, used ( a more recent version ). Any sellers?