The mobile service providers own the numbers, even if you move your number to another provider and then cancel your contract, the number would revert back to the original provider. I think you would have more rights to actually own your number if you are on a pay as you go contract as long as you stay within the contractual agreement for usage. If you are asking can you sell the number, most service providers don't care who pays the bill as long as they agree to swap the contract to someone else first..........