Roy, chairman of the Sahara conglomerate, was initially given 10 days by the Supreme Court to talk to potential bidders for three hotels, including Grosvenor House in London and the New York Plaza, to raise $1.6 billion for bail.
Roy has been given an office with 600 sq ft (56 sq metres) of space inside New Delhi's Tihar jail complex, where he can hold video conferences, use computers and receive visitors to try to sell or mortgage the hotels.
The initial deadline for using these facilities is set to end on Aug. 20. Keshav Mohan, a lawyer for Sahara, told Reuters on Wednesday that a 15-day extension had been sought for continued use of the facilities in prison.
"The court is likely to hear the matter tomorrow," Mohan said.
A spokesman for Sahara declined to comment on the extension request.
Roy was jailed in March after he failed to appear at a contempt hearing in the long-running dispute with the capital markets watchdog over the company's failure to repay billions of dollars to investors who were sold outlawed bonds.
He has yet to be charged over the dispute and denies any wrongdoing. His Sahara group has vast real estate, media and hotel interests, part-owns a Formula 1 team and used to sponsor the Indian cricket team.
Roy calls himself "managing worker and chairman" of Sahara and chief guardian of the "world's biggest family", overseeing businesses with almost a million staff and agents.
(Reporting by Suchitra Mohanty and Devidutta Tripathy; writing by Sumeet Chatterjee; Editing by Shadia Nasralla)
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