Brothers property dispute

I purchased properties more than 20 years ago. Purchase was executed in following manner : Agreement to Sell & Purchase, Will, Receipt are in my name and GPA ( in some cases SPA also) are in the name of my brother. In good faith the files were handed over to my brother but now he refuse to return the files and is asking for a 50% share Question : 1. How can I get my files back. 2. What is my lawful position in these properties. 3. Can he demand any share?