The Enterprise license is for you if either:
  1. you want to install on unlimited servers, for single or multi-site installations
  2. you are a private company that turns over $20,000 a year or more, or an organization with an annual budget of more than $20,000 (or equivalent in your currency)

Annual Licence

This licence is renewed annually.

Re-sellers

If you are purchasing on behalf of a customer, no problem - but the licence will be held by you as the purchaser.