All standard OptimizePress licenses are for personal use only (this means no use for client sites or sites built to sell).
We do now have developer license packages available to purchase - To access our developer license package options, you must hold an active OptimizePress license (core package or above).
Once you are in your OptimizePress account you will find a link to the developer packages from the licensing page. The developer licenses are sold in packs of 5 - these special licenses CAN be used on client sites.
If you require further information please contact our support team who will be happy to advise further on the options available