Bengaluru/Mumbai, Sept. 18 -- Tata Trusts chair Noel Tata presented a Shapoorji Pallonji (SP) Group proposal to the Tata Sons board on Thursday, wherein the minority investor offered to sell up to a 3% stake back to the holding company for Rs.25,000 crore. According to an executive familiar with the matter, the SP Group has offered this as an alternative to making Tata Sons a publicly listed company-something the minority investor has demanded for long-and comes after the Reserve Bank of India ordered it to go public on Friday. The Tata Sons board convened at the meeting room on the fourth floor of Bombay House at 10.30 am, primarily to discuss two thorny issues: the course of action after the RBI order, and the tenure of its current chair N. Chandrasekaran. Tata presented the SP offer in the afternoon, the executive said seeking anonymity. SP Group made this offer in a letter sent last week to Farokh Subedar, an aide to Tata, the executive said. Subedar, along with Ankur Verma, group chief strategy officer at Tata Sons, and a senior SP Group representative, forms a panel to resolve issues among Tata Sons, Tata Trusts and SP Group. The panel is believed to have met at least twice in the last 15 months but made little progress. In its letter, SP Group asked for Rs.25,000 crore for 2-3% of Tata Sons shares, which values the holding firm at Rs.8.3 trillion at this price. SP Group expects this money over 18 months, the executive said. Tata Group has not conducted any independent valuation exercise for Tata Sons, which owns stakes in 26 listed companies and also runs privately held businesses. The executive dismissed concerns that SP Group might withdraw its offer, since it was made before the RBI order on 11 September. He said a public listing would value Tata Sons at 30-35% below the total value of its businesses, meaning SP Group would need to sell that many more shares to raise the same Rs.25,000 crore. This is a so-called holding company discount-where the stock market values a parent company below the combined worth of everything it owns. "Any planned IPO is an uncertain, complex and slow process. Also, we don't know how the value is decided or if there is a discount when Tata Sons goes public. So, you could say that SP Group's offer might be good for them since they need money in the next 18 months," said an executive....