ACI will buy back from IBM warrants for purchasing about 2.5 million ACI shares.
ACI had said last week that IBM will start exercising its 2.8 million warrants to take a stake in the company.
International Business Machines Corp, one of the largest computer hardware makers in the world, received the warrants in December 2007. The warrants allow it to buy up to 8 percent of ACI shares.
ACI shares closed at $43.08 on the Nasdaq on Friday.
Reporting by Sharanya Hrishikesh in Bangalore; Editing by Sreejiraj Eluvangal