TCS have told shareholders their systems were not compromised in the hack of M&S.
As an explainer here (not in the article): TCS IT systems weren't compromised. Their helpdesk service (they're AD admins at M&S) was used to gain access to M&S. They manage M&S IT systems.
https://www.reuters.com/business/media-telecom/indias-tcs-says-none-its-systems-were-compromised-ms-hack-2025-06-19/