"This is an unfortunate event and not something that we are very pleased about, especially as Mattel has been pursuing the matter in Indian courts for the past few months," Scrabulous co-creator Rajat Agarwalla told AFP.
"We sincerely hope to bring our fans brighter news in the days to come."
Scrabulous.com was launched by brothers Rajat and Jayant Agarwalla in India in 2005 and rocketed to popularity two years later after they released a version as a free "add-on" application for Facebook.
More than 500,000 people reportedly played the online word game daily on Facebook.
Facebook confirmed that Agarwalla and his brother disabled the Scrabulous application as a result of a legal demand from Hasbro, which owns the Scrabble trademark and copyright in the United States and Canada.
"We have had to restrict our fans in the USA and Canada from accessing the Scrabulous application on Facebook until further notice," Agarwalla said in an email exchange.
Hasbro on July 25 filed a lawsuit in US federal court against Scrabulous and sent a notice demanding Facebook remove the popular game from the hot social-networking website.
Toy and game manufacturers Hasbro and Mattel, which share ownership of the Scrabble trademark, asked Facebook in January to remove the renegade online version of its game from the website.
"Our hope and expectation is that the parties can resolve their disagreements in a manner that satisfies the parties, that continues to offer a great experience to gamers and that doesn't discourage other developers from using our platform to share creativity and test new ideas," Facebook said.
Filing of the civil suit came a week after videogame colossus Electronic Arts released, with Hasbro's blessing, a free online Scrabble game customized for Facebook websites in the United States and Canada.