HDFC Bank has moved to contain governance concerns triggered by the sudden resignation of its erstwhile part-time chairman and independent director, Atanu Chakraborty, appointing external law firms to review the circumstances behind his exit on differences over “values and ethics”, but lacking further details.

The abrupt departure has sparked questions around corporate governance standards and the accountability of independent directors, especially after the bank’s shares came under pressure.

Two domestic firms — Trilegal and Wadia Ghandy & Co — along with a US-based law firm, have been engaged to undertake an independent review.

“To reinforce the robust governance standards of the bank, the board of directors at its meeting held on March 23, 2026, approved the appointment of external law firms (domestic and international) to conduct a review regarding Mr Chakraborty’s resignation letter,” the bank said in a filing on Tuesday. The firms have been asked to submit their report within a reasonable timeframe.

The bank also clarified that Chakraborty “did not mention any happenings and practices which were not in congruence with his personal values and ethics” in his resignation letter.

A spokesperson described the move as a proactive step aimed at ensuring an objective, fact-based assessment of the issues raised, and reiterated the bank’s commitment to benchmarking itself against the highest governance standards it has followed over the decades.

The lack of specific disclosures in the resignation has surprised not just the board but also regulators. Sebi chief Tuhin Kanta Pandey said any insinuations must be supported by proper evidence in the interest of minority shareholders.

“Nobody is expected to make any insinuations without proper evidence and recording,” Pandey said, cautioning that such remarks could impact shareholder interests. He added that independent directors must exercise responsibility in what they state and formally record.

Chakraborty, however, told Reuters that his letter did not make any insinuations.

Earlier, interim chairman Keki Mistry had suggested that the resignation may have stemmed from “relationship issues” with the executive leadershipnternal controls remain stable.

A former president of the Institute of Chartered Accountants of India told The Telegraph that while there is no formal obligation, organisations committed to strong governance can place such disagreements among board members on record in the minutes of the board meetings.

Shriram Subramanian, founder of InGovern, a corporate governance research and proxy advisory firm, told CNBC-TV18 that independent directors are also accountable to both the company and its shareholders, adding that the resignation letter was “quite cryptic” and could have been more detailed.