Currently, we are selling a reporting type application which is partly based on ExtJS, and occasionally some of our customers want to customize those aspects of our application which requires using the ExtJS API.
Until now, we told them to buy a developer license themselves or delegated the job to our developer who has a valid Ext license.
Is there anyway we could pre-purchase additional developer license for our customers without telling them they should buy another license besides our own product license?
If there's such an option (like an OEM license) available, how much it would cost us?