The Scrabulous game, which was developed by Indian brothers Rajat Agarwalla and Jayant Agarwalla, has become a big money earner for the pair.
It has been claimed that the brothers are receiving $US25,000 ($A27,853) per month in advertising revenue from Facebook.
According to Fortune magazine, Hasbro sent a cease-and-desist notice to Facebook asking them to remove the application.