We usually don't allow transfer of a license.
The only exception is when the same client/shop is changing domain name and closing down the old shop.
If this is the case, please email us at firstname.lastname@example.org confirming that:
1) the domain/ shop in the original order is closing down and will never be used as a live shop
2) both original and new shops are 100% owned by one and the same company, including some documentation e.g a whois record.
If both shops are live, please refer to this article: Requesting serial keys for new domains