Billionaire Pallonji Mistry, Chairman of diversified Shapoorji Pallonji (SP) Group, died in the wee hours of Tuesday here, company officials said. Mistry, whose SP Group is the largest shareholder in the Tata Group with 18.37 per cent holding in the over USD 100 billion conglomerate, was 93. India-born Mistry died mid-sleep at 0100 hrs at the family residence in South Mumbai, they said. He had acquired Irish citizenship.