NEW DELHI: A group of foreign institutional investors (FIIs) that together own more than 10% of Tata Motors has written to the board expressing concerns about the possibility of Tata Sons being given preferential access to strategic information ahead of other investors, according to persons directly aware of the matter.The letter makes no reference to the recent sacking of Cyrus Mistry as chairman of Tata Sons in a boardroom putsch that saw Ratan Tata return to the helm of the holding company. But its despatch appears to have been sparked by revelations made by Mistry — who remains chairman of Tata Motors — defending his record and blaming decisions by Ratan Tata for the group’s performance.The group of investors that wrote the letter is said to include certain large US-based FIIs, an activist shareholder and sovereign wealth funds. Some of the investors hold Nasdaq-traded American Depository Receipts (ADRs) of Tata Motors.Big overseas investors in Tata Motors include UK’s Legal and General, US-based Oppenheimer Fund, Sweden-based Nordea Asset Management, Abu Dhabi Investment Authority, Government of Singapore Investment Corp and Monetary Authority of Singapore.They are also among the largest FIIs investing in Indian equities. The note to all directors elaborated on the responsibilities of a publicly traded company’s board, said the people cited above.Directors are duty bound to keep information of strategic relevance within the confines of the board, it said, adding that all shareholders should be privy to the same level of information at any given point in time.The letter makes no reference to any action being contemplated by the investors. A Tata Motors spokesperson declined to comment. ET couldn’t independently verify the identity of the investors that have written the joint letter.The concerns surfaced in the backdrop of reports that Tata Motors kept Ratan Tata informed of product plans with respect to the Nano and that board decisions had the backing of Tata Sons. Ratan Tata’s dream project was kept alive despite losing money heavily, Mistry said in his October 25 note."Historically, the company had employed aggressive accounting to capitalise substantial proportion of the product development expenses, creating a future liability," Mistry said. "Beyond this, the Nano product development concept called for a car below Rs 1lakh, but the costs were always above this. This product has consistently lost money, peaking at Rs 1,000 crore."Mistry said it would have made financial sense to kill the car. "As there is no line of sight to profitability for the Nano, any turnaround strategy for the company requires to shut it down. Emotional reasons alone have kept us away from this crucial decision," he said. "Another challenge in shutting down Nano is that it would stop the supply of the Nano gliders to an entity that makes electric cars and in which Mr Tata has a stake."Some of the investors seemed uncomfortable with amendments to the articles of association that Mistry mentioned, although they didn’t make any specific reference to this in the letter, said the people cited above.Mistry said this "changed the rules of engagement between the Trusts, the board of Tata Sons, the chairman and the operating companies". The Tata Trusts are the majority shareholder in Tata Sons while the Mistry family’s Shapoorji Pallonji Group comes next with 18.5% stake in the holding company. ET reported on October 26 that Mistry had to seek approval from Tata Sons for all capital expenditure exceeding Rs 500 crore at any of the group companies.Insider trading rules bar "asymmetry of information" in a publicly traded company, said Souvik Ganguly of Acuity Law."Accordingly, any one shareholder/investor in a publicly traded company should not seek any special information rights vis-a-vis other shareholders/investors," the lawyer said. "Any contract or bilateral arrangement between any investor and a publicly traded company for seeking prior information on strategic decisions may not be enforceable as such contract or arrangement may fall foul of the prohibition of insider trading regulations of Sebi (Securities and Exchange Board of India)."Promoters held a 33% stake in Tata Motors as per stock exchange filings for the period ended September, a bulk of this through Tata Sons, while FIIs held 26%. About 18% of the company’s shares are in the form of ADRs.The 11-member Tata Motors board led by chairman Mistry includes six independent directors — Nusli Wadia, Subodh Bhargava, Nasser Munjee, Phalguni Nayar, Vinesh K Jairath and Raghunath Mashelkar. Jaguar Land Rover Chief Executive Officer Ralf Speth, who was recently elevated to the Tata Sons board, is also a director. Other members are CEO Guenter Butschek, Ravindra Pisharody, executive director, commercial vehicles, and Satish Borwanker, executive director, quality. The board is scheduled to meet on November 14 to consider September quarter earnings.