A Chatham man who is locked in a legal battle for half of a $6-million lottery prize is reported to have launched a lawsuit against the provincial lottery regulator. 

Maurice Thibeault is seeking a total $825,000 in damages from the Alcohol and Gaming Commission of Ontario.

In a claim filed in Windsor, Thibeault alleges the commission didn't collect or analyze potential evidence in an investigation.

Thibeault received half of the sum in January after his former live-in partner filed a separate statement of claim over the lotto 6/49 prize.

A lawyer for Denise Robertson claims Thibeault broke up with her -- then within a week  tried to claim the total $6.1-million prize.

Robertson claims they always bought tickets together and shared the winnings for the two years they were together.

The court is determining the rightful owner.