I must determine if you'll be able to add security to some WordPress theme offered online (something similar to an item license)?
I wish to make certain that when a style is offered, the customer are only able to apply it themself and never transfer or re-market it.
This can be a violation of the WordPress GPL license.
This does not always need to be a breach from the WordPress GPL license ...
Victor did not point out that he'd release it using blogging platforms.net - and there is commercial plug-inches and styles too.
The easy way make this happen is ionCube (or similar PHP encoders / code shields) + a vital-file certain to domain title.
But remember that this is not one hundredPercent secure solution, since it may be unwrapped / decoded very quickly.
Another method could be type of certification server - which triggers per domain-title - or transmits out 1 missing file upon effective activation.
No its acutally the oppocite. A Wordpress theme can be the source of vulnerabilities.