Sigma Advanced Systems reports three board exits November 6

Sigma Advanced Systems Limited disclosed that three directors resigned at the end of business on November 6, 2026, including two independent directors, with all three stating that their exits did not arise from disagreements with the board or management; the cited reasons were professional commitments, other engagements or other preoccupations.

Which Sigma Advanced Systems directors resigned on November 6?

Sigma Advanced Systems said Suryanarayana Raju Nandyala, Leona Ambuja and Uma Garimella ceased as directors at the end of business on November 6, 2026. Nandyala and Garimella were independent directors, while Ambuja was a non-executive non-independent director. The company recorded the three changes in separate resignation letters and annexures dated November 6, 2026.

The individual letters state that the resignations would take effect at the conclusion of the board meeting scheduled for November 6, 2026, while the annexures specify end of business hours on that date. Nandyala was identified as an independent director, Garimella as an independent woman director, and Ambuja as a non-executive director in the formal disclosures.

Why did the three Sigma Advanced Systems directors leave?

Sigma Advanced Systems said Nandyala resigned because increasing professional commitments and other engagements meant he could not devote the time required for board responsibilities. In his November 6, 2026 letter, Nandyala said he was satisfied with the company’s leadership and management, and confirmed that no other material reason underlay his decision.

Garimella gave a similar explanation in her November 6, 2026 letter, saying increasing professional commitments and other engagements prevented her from devoting the requisite time to her independent-director responsibilities. Her annexure identifies the same reasons for her resignation as independent woman director at the end of business on that date.

Ambuja’s annexure stated that she resigned from her non-executive role because of other preoccupations. Her November 6, 2026 letter said there were no other material reasons beyond those stated, distinguishing her stated reason from the time-availability explanations given by Nandyala and Garimella.

Did the departing Sigma Advanced Systems directors report disagreements?

Sigma Advanced Systems disclosed that none of the three departing directors cited a disagreement with the board or management. Nandyala and Garimella each expressly said that they had no concerns or disagreements requiring disclosure to stock exchanges in their November 6, 2026 letters.

Nandyala also thanked the board and management, stating that timely information and data had been provided when sought. He said the chairman had steered board meetings well, but that observation was Nandyala’s statement in his resignation letter rather than a quantified company performance disclosure.

Ambuja separately confirmed that her November 6, 2026 resignation was not on account of any disagreement with the board or management. Taken together, the three disclosures describe the departures as resulting from professional demands or other preoccupations, rather than a disclosed dispute over the company’s operations, strategy or governance.

How do the resignations fit Sigma Advanced Systems’ other board changes?

Sigma Advanced Systems disclosed the three exits on the same November 6, 2026 date on which its board approved executive-role changes for Kartheek Raju Chintalapati and Sunil Kumar Kalidindi. Chintalapati’s designation was approved to change from non-executive director to whole-time director, and he was designated vice chairman of the board.

Chintalapati’s whole-time director appointment was proposed for five years from November 6, 2026, subject to shareholder approval at the ensuing general meeting. The vice chairman designation was effective from the same date. The company said Chintalapati has more than 15 years of international consulting and investment experience and has led the iLabs Family Office for the past decade.

The board also approved Kalidindi’s redesignation from whole-time director to managing director for five years from November 6, 2026, subject to shareholder approval. Sigma Advanced Systems said Kalidindi had headed the company as executive director and chief executive officer since December 2021, with responsibility for operations and for organic and inorganic strategy in aerospace and defence.

What does the November 6 change mean for board composition?

Sigma Advanced Systems lost two disclosed independent-director positions on November 6, 2026: Nandyala’s independent directorship and Garimella’s independent woman directorship. Ambuja’s departure was from a non-executive non-independent position, making the day’s three exits span both independent and non-independent board roles.

The filing does not provide a post-resignation board size, a before-and-after count of independent directors, or names of successors for the three departing directors. It therefore documents the effective date and roles of the exits, but leaves the resulting board composition unresolved in the supplied announcement.

The same disclosure stated that Chintalapati and Kalidindi were not related to any directors and were not debarred from holding director office by an order of the Securities and Exchange Board of India or another authority. Those confirmations accompanied their proposed or approved redesignations, rather than appointments to replace the directors who resigned on November 6, 2026.

Conclusion

The November 6, 2026 announcement records three simultaneous board departures at Sigma Advanced Systems, including two independent directors. Nandyala and Garimella cited increasing professional commitments and other engagements, while Ambuja cited other preoccupations; each director said the exit was not due to disagreement with the board or management.

The next disclosed event is the ensuing general meeting, where shareholders are to consider Chintalapati’s five-year whole-time director appointment and Kalidindi’s five-year managing director appointment. The company has not disclosed replacements for Nandyala, Ambuja or Garimella, so the future composition of the board remains to be clarified.