The founder of Satyam Computer Services, Ramalinga Raju, who was found guilty in an accounting fraudcase and sentenced to seven years' imprisonment last week, has filed an appeal to challenge the court's verdict.

Uma Maheshwar Rao, a lawyer for Raju, told Reuters the appeal was filed in a sessions court to "question the very finding of the case," but did not give other details.

On Thursday, a court in Hyderabad pronounced Raju, a management graduate from Ohio University who founded Satyam in 1987, guilty of forging documents and falsifying accounts in what was among India's biggest corporate frauds.

Raju admitted in January 2009 in a five-page letter that Satyam's profits had been overstated for years and assets falsified in a fraud allegedly worth over $1.5 billion, bringing the company to the brink of collapse.

(Reporting by Nivedita Bhattacharjee in Mumbai; Editing by Biju Dwarakanath)