Bought a property with litigation

Hi experts, I purchased a land in Bangalore back in 2012 July. The titles were found to be clear as was stated by our lawyer. However when the original documents were handed over to me, I noticed one case document in it. Further investigating in to the case was revealed that there is a problem with first owner(I am 5th Owner now), where in the land was sold only based on verbal partitioning done with in the family. The son sold the property to previous owner. whereas the property was belonging to Mother. Khata was under son's name. An appeal was raised by mother about this. The case was taken up in lower courts where the judgment was given in favour of the son who sold the property. however in High court the judgment was passed to mother. after this in two years time mother passed away. so the son now might be the full heir to mothers property. Now my question is in light of the last judgment what is my legal standing here? and what can I do to have a legal possession of this property? Anees.