On May 6, 2011, David P. sold the Namecoin name d/radio for 5BTC and stamped the "SOLD" mention in the operation's value when broadcasting name transfer, forever linked to the name’s values history, onchain. 

This marked the history’s first non-fungible asset transfer on a blockchain.

Full doc:

On May 6, 2011, David P. sold the Namecoin name d/radio for 5BTC and stamped the "SOLD" mention in the operation's value when broadcasting name transfer, forever linked to the name’s values history, onchain. 

This marked the history’s first non-fungible asset transfer on a blockchain.

Full doc: https://t.ly/kW0FZ