The Times of India, quoted an anonymous government official as saying, "India may become party to the lawsuit and provide evidence to the New York court. The matter can be taken up at the government-to-government level as well in support of the lawsuit under existing Mutual Legal Assistance Treaty (MLAT) between India and US."
In the case filed in Nov 2011, the plaintiff have said, "The ISI has long nurtured and used international terrorist groups, including the LeT, to accomplish its goals and has provided material support to the LeT and other international terrorist groups." The lawsuit referred to the disclosure made by American-Pakistani Lashkar terrorist David Coleman Headley and blamed top ISI officials for providing "critical planning, material support, control and coordination of the attacks (26/11)".
The case was filed by the relatives of Rabbi Gavriel Noah Holtzberg and his wife Rivka who were killed during the 26/11 attacks by Lashkar terrorists at Chabad House in Mumbai. They have accused the ISI of "critical planning, material support, control and coordination of the attacks (26/11)".
Following the law-suit the court in New York had summoned senior ISI officials including its chief, Major General Ahmed Shuja Pasha, and LeT leaders Hafiz Saeed and Zakiur Rahman Lakhvi.
Times of India has quoted another anonymous official as saying, "The latest disclosure made by Headley's accomplice Tahawwur Hussain Rana that he acted at the behest of the Pakistan government and ISI has strengthened India's position."
It seems that India might do whatever is possible, to strengthen the case of the petitioners to expose the ISI and to encourage relatives of the other foreign nationals also who were killed in the attacks to start similar lawsuits against the ISI.
28 foreigners including citizens of France, UK, Germany, USA, Singapore, Israel, Canada, Australia and Japan were killed by the terrorists in the 26/11 attacks.