Resignation issues

Hi, I'm working with an MNC since July 16, 2012 and have resigned recently on July 16, 2015. On July 20 I was moved to bench (relieved of any assignments and was having no tasks assigned). Even though I've given all the knowledge to the backup resource and have completed my assignments, my employer is forcing me to serve 90 days notice period. I've 47.5 leaves in my account, which could be adjusted in my notice period, other wise I'm ready to buy-out the notice period as stated in my appointment later "your services will be confirmed in writing by the company and thereafter, subject to any other agreement or understanding between you and the Company, either party can terminate this employment by providing a notice period of three months, or payment of basic pay in lieu of such notice, to the other party." Even though i'm ready to pay the lieu amount, the employer is behaving like a dictator and says that the right to decide notice period or pay in lieu is in Company's hand. Please provide help to me on this. I would like to know if I present all the proofs of the situations stated above, can I make it a legal case against the employer. and would it be strong enough to get me through ?