Your information turns the case even more difficult. You were supposed to receive the 5 BTC, but you confused the receiving address. That means the 5 BTC was owned by another user and not by you. In this case, how can you prove that? What evidence you have that the another owner should send the 5 BTC to you?
If it helps anything, I could ask the other user to post here. This was part of a deal, with the 5 BTC being part of the payment.
Yes, it helps, please ask him to post a good evidence that he owns the address.
So the address 1JYC3GbbhHiYKkZkPV2PhsdYPPDAUjjomS is owned by you? Do you receive funds from Deepbit mining pool?
Yes it is and yes I did.
Excuse me, but was has my original question (who owns this adr.?) to do with which pools I mine on?
Is 1Nbjpo1tkeayJ28me2kNcZ3ZoqBQHJqoAx owned by you?
It was a question just to proof your claim. No, I do not own the 1Nbjpo1tkeayJ28me2kNcZ3ZoqBQHJqoAx address, and if I did, you would have your 5 BTC back since I am not entitled to receive 5 BTC from any source.
1.

2.

3.
http://blockchain.info/taint/1Nbjpo1tkeayJ28me2kNcZ3ZoqBQHJqoAxhttp://blockchain.info/taint/1Nbjpo1tkeayJ28me2kNcZ3ZoqBQHJqoAx?reversed=trueThe address which received the funds from the another user, 1Nbjpo1tkeayJ28me2kNcZ3ZoqBQHJqoAx, is probably managed by a user which also obtain funds from the Deepbit mining pool (1). This user have already sent funds to Butterfly Labs or Bit-Pay (2):
https://bitcointalk.org/index.php?topic=90972.msg1001729#msg1001729https://bitcointalk.org/index.php?topic=90972.msg1001850#msg1001850The address was also used to send funds to an address listed in the znort987's
Bitcoin 500 richest addresses, updated often thread (3):
https://bitcointalk.org/index.php?topic=92423.msg1018953#msg101895317517.99900000 fe0c68e8a74f730aa33487958bfc923f9e6f66b5 1QAHVyRzkmD4j1pU5W89htZ3c6D6E7iWDs Thu Sep 6 04:05:37 2012