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I don't have any licence as far as I'm aware, since one is not necessary for using Quartus web edition with Cyclone V.
http://www.altera.com/download/licensing/setup/lic-setup-q2webedition.html tells me:
It seems the same does not apply when using OpenCL with the Cyclone V?
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I'm not certain, but OpenCL and/or Cyclone V devices may require a license at the moment. Since DSP Builder says it requires a license, it makes sense that OpenCL would as well since they're both HLD tools. You may wish to check this with your local FAE.