Change in Auditors

Corporate Office: Registered Office: Star 1, Opp IIM Bangalore, Bilekahalli, Cyber One, Unit No. 902, Sector 30A, Bannergha(cid:425)a Road, Bengaluru – Plot No - 4 & 6, Vashi, 560076, India Navi Mumbai - 400703, India T: +91 80 6784 0738 T: +91 22 2789 2924 Date: September 23, 2026 BSE Limited National Stock Exchange of India Ltd Phiroze Jeejeebhoy Towers Exchange Plaza, Bandra Kurla Complex, Dalal Street, Mumbai- 400001 Bandra (E) Mumbai – 400051 Scrip Code: 544292 Symbol: ONESOURCE Dear Sir/ Madam, Subject: Intimation of appointment of the statutory auditors of the Company in terms Regulation 30 of the SEBI (Listing Obligations and Disclosure Requirements) Regulations, 2015 (“SEBI Listing Regulations”) In continuation to the intimation regarding the outcome of the Board meeting dated May 13, 2026, this is to inform the exchange(s) that the shareholders in the 19th Annual General meeting held today, i.e. Wednesday, September 23, 2026, appointed M/s B S R & Co LLP, Chartered Accountants (Firm’s Registration No.:101248W/W- 100022), as Statutory Auditors of the Company, to hold office for a period of 5 (five) consecutive years from the conclusion of the 19th Annual General meeting until the conclusion of the 24th Annual General Meeting of the Company- Disclosure pursuant to Regulation 30 of the SEBI Listing Regulations., read with SEBI Master Circular No. O/49/14/14(7)2025-CFD-POD2/I/3762/2026 dated January 30, 2026, enclosed herewith as Annexure A. The resolution has been duly passed as per the final draft Scrutinizer’s report. The results will be submitted to the stock exchanges on or before Friday, September 25, 2026. This is for your kind information and record purposes. For and on behalf of OneSource Specialty Pharma Limited Trisha A Company Secretary and Compliance Officer Membership Number: A47635 OneSource Specialty Pharma Limited info@onesourcecdmo.com | www.onesourcecdmo.com CIN: L74140MH2007PLC432497 Corporate Office: Registered Office: Star 1, Opp IIM Bangalore, Bilekahalli, Cyber One, Unit No. 902, Sector 30A, Bannergha(cid:425)a Road, Bengaluru – Plot No - 4 & 6, Vashi, 560076, India Navi Mumbai - 400703, India T: +91 80 6784 0738 T: +91 22 2789 2924 Annexure – A Disclosure pursuant to Regulation 30 of the SEBI (Listing Obligations and Disclosure Requirements) Regulations, 2015, read with Circular No. HO/49/14/14(7)2025-CFDPOD2/I/3762/2026 dated January 30, 2026 Sl. Particulars Description Statutory Auditor 1. Reason for change viz. appointment, Appointment of M/s BSR & Co LLP (Firm’s re-appointment, resignation, removal, Registration No.:101248W/W-100022), as the death or otherwise. statutory auditors of the Company to hold office from the conclusion of the 19th Annual General Meeting for a term of 5 (five) consecutive years, i.e., until the conclusion of the 24th Annual General Meeting. 2. Date of appointment/ re September 23, 2026 appointment/cessation (as applicable) and terms of appointment and re appointment 3. Brief profile in case of appointment M/s B S R & Co. ('the firm') was constituted on 27th March, 1990 as a partnership firm having firm registration no. as 101248W. It was converted into Limited Liability Partnership i.e. B S R & Co. LLP on 14th October, 2013 thereby having a new firm registration no. 101248W/W-100022. The registered office of the firm is at 14th Floor, Central B Wing and North C Wing, Nesco IT Park 4, Nesco Centre, Western Express Highway, Goregaon (East), Mumbai - 400063. B S R & Co. LLP is a member entity of B S R & Affiliates, a network registered with the Institute of Chartered Accountants of India. It has its head office in Mumbai and operates through 14 locations across India. M/s. B S R & Co. LLP has a strength of over 4,000 personnel and 170 partners and serves as statutory auditor to several companies listed on stock exchanges in India including companies in the Pharma and Life Sciences sector. 4. Disclosure of relationship between Not Applicable directors (in case of appointment of director) OneSource Specialty Pharma Limited info@onesourcecdmo.com | www.onesourcecdmo.com CIN: L74140MH2007PLC432497