I am getting sued for title of property

Hello Experts, Till 2007, I was the proprietor of my firm ( Owner of land and business).In 2008, the business was in a loss and my health was also not good. So I made new partners who were very close to me. I executed partnership deed and retired myself and submitted the documents in the registrar of firms. so that I can save the business. But they frauded me and the business was shut down. This all happened due to trust Now they are suing me in Civil court for the title of the land from past many years. Q) So my question is in Indian Law, is it possible to grab the property by just executing partnership deed? While doing my research I came to know about Indian registration act 1908 section 17 which states that the Title/Ownership the land cannot be changed without doing registration of land if the cost of land is above 100 Rs Is it true? Because They are suing me for Title of land and no registry is done, no stamp duty is paid.No payment is done.