Lets not get bogged down with legal speak, here are our simple terms and conditions:

• One licence gives you the right to use the software on any umbraco installation associated in the production of the website located at the specified domain
• A licence is non-transferable, and cannot be used for multiple clients or sites not considered to be part of a single deployment chain
• We own the code, and you can't modify it, steal it, crack it or try to pass it off as your own
• We reserve the right to revoke a licence if we think it has been misused, sold on, stolen etc
• We accept no responsibility for the any loss of data, content, setting or anything else bad through the use of this software

Our full licence terms are available here.