Closure of Trading Window for the Quarter Ended 30th September, 2026 (Q2)

CS:01:100/26-27 24th September 2026 The Secretary National Stock Exchange of India Limited BSE Ltd. Exchange Plaza, 5th Floor Phiroze Jeejeeboy Towers Plot No.C/1, G-Block 25th Floor, Dalal Street Bandra Kurla Complex, Bandra (E) Mumbai – 400 001 Mumbai – 400 051 Dear Sir, Sub: Intimation of Window Closure Period - CHENNPETRO / 500110 / INE178A01016 - - - - - Pursuant to the SEBI (Prohibition of Insider Trading) Regulation, 2015 and as per the Code for Prevention of Insider Trading in the Securities of CPCL, it is hereby notified that the trading window for dealing in securities of CPCL shall remain closed for “Insiders” of CPCL from 1st October, 2026 (Thursday) till 48 hours after the Financial results for the Quarter ended 30th September 2026 are filed with exchanges. The date of the Board Meeting for consideration of the above financial results would be intimated in due course. The above is for your information and record please. Thanking you, Yours faithfully, for Chennai Petroleum Corporation Limited Lalit Kumar Mohanty Company Secretary