Office workers may soon be deprived of a favoured means of whiling away the tedious hours between 9 and 5 – playing Scrabulous on Facebook.

The makers of Scrabble have said they plan to launch an official version game on the social networking site later this month, paving the way for the demise of the enormously popular but unsanctioned alternative.

Earlier this year, Hasbro and Mattel, the toymakers that jointly own the rights to Scrabble, provoked protests from Scrabulous fans by demanding that Facebook take down the application. About 450,000 people play Scrabulous on Facebook every day.

Hasbro and Electronic Arts (EA), the video game company which is making the official version, have not said what action they will take in relation to Scrabulous, which was produced for Facebook by two brothers based in India.

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It is understood that the companies did not press a legal case against Scrabulous because of the potentially angry reaction from fans who would be left without a version of the game on Facebook.

Scrabble fans in the US and Canada can get a taste of the official version at Pogo.com, a games website which launched the game yesterday. The Facebook version will be available later this month, Hasbro and EA said in a statement. The companies did not say when the game will be launched outside the US.

Asked what Hasbro planned to do about Scrabulous once an official version of Scrabble was launched, a Hasbro spokesman said: "Hasbro has been consistent in stating that Scrabulous infringes on our intellectual property and we are keeping our legal options open."

In January, Mattel, which owns the rights to Scrabble outside the US, wrote to Facebook asking it to take down the Scrabulous application, saying that it valued its intellectual property and "actively protected" its brands and trademarks.

But within hours of the news breaking, thousands of players joined a "Save Scrabulous" group on Facebook, with many of them claiming that Scrabulous had contributed to a renewed popularity of the board game. "Scrabulous has massively raised the profile of Scrabble, rendering it actually quite cool (where it was once seen as rather geeky)," one Facebook user in London wrote.

Mattel apparently did not follow up its demand, and Facebook did not take Scrabulous down. The application, which was made as an 'add on' for Facebook by Rajat and Jayant Agarwalla, two software developers based in Calcutta, has remained playable ever since.

Mattel was no immediately available for comment.

Jayant Agarwalla told Times Online today: "We strongly believe that people should have the option of playing what they like, rather than be forced by developers into using something they offer only for monetary gains." Mr Agarwalla declined to comment on whether Hasbro had brought a legal action against Scrabulous.

A spokesman for Facebook was unavailable.

Earlier this year, Mr Agarwalla was quoted by Fortune magazine as saying that lawyers from the various parties were working on a solution to the dispute. The brothers have admitted to earning $25,000 (£13,000) a month from advertising on the application.

The Association of British Scrabble Players has said that nothing has done more to get young people interested in playing Scrabble in the past five years than the Scrabulous application on Facebook. "Many of our members use it," a spokesman said.

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