I dont know. But most scratch offs games have an expiration date. Most state lotteries issue and run a scratch off game for a limited time period and after that particular game has ended, there is a time limit in which to claim the prize and 6 years seems way too long. Also IIRC, when a scratch off game ends, the retailer has to turn in the unsold tickets. All lottery tickets have unique serial numbers on them so that is how the lottery officials know how many winning tickets are unclaimed and publish how many winning tickets are unclaimed and publish the deadlines for claiming the prize.
More info on the story at the following article. The article states the ticket was purchased in Oct. 2006 and was a $250,000 annual payout over 20 years. They have been in contact with the orginal purchaser it seems and charges have been filed against the two brothers.
http://www.journalgazette.net/article/20121113/NEWS03/121119777/1066/news03
Another article:
http://www.syracuse.com/news/index.ssf/2012/11/syracuse_brothers_lottery_ticket_arrested.html