The Spanish city of Coruna has begun a search for the person who missed out on $6.3 million US by buying a winning lottery ticket but leaving it behind in the shop.

The winning ticket for June 30, 2012, was discovered by the owner of the lottery shop who, after keeping it for a year in the lost and found box, decided to scan it before throwing it away.

Shop owner Manuel Reija told a Galician TV station: "I couldn't believe it the first time I checked the ticket so I checked it again just in case there was a computer error. I was standing up but I had to sit. I almost broke the chair."

Reija will get to keep the money if no one responds to a notice on the website of Coruna's town hall urging the winner to come forward. Claimants have been told to expect tough checks.