Press Release

www.stl.tech July 17, 2026 National Stock Exchange of India Limited BSE Limited Exchange Plaza, 5th Floor, Phiroze Jeejeebhoy Towers, 25th Floor, Plot No. C-1, G Block, Dalal Street, Fort, Bandra Kurla Complex, Bandra (East) Mumbai – 400001 Mumbai – 400051 Scrip ID - STLTECH Scrip Code - 532374 Sub: - Press Release – STL expands its optical connectivity portfolio in the US with the CONCAT solution. Ref.: Regulation 30 of the SEBI (Listing Obligations and Disclosure Requirements) Regulations, 2015 Dear Sir/Madam, A US subsidiary of the Company, STL Optical Connectivity NA, LLC, today announced the launch of its new advanced FTTH solution, CONCAT after successfully completing field trials on the networks of one of the largest telecom service providers in the United States. A copy of the press release in this regard is enclosed herewith. Kindly take the above on record. Thanking you. Yours faithfully, For Sterlite Technologies Limited Mrunal Asawadekar Company Secretary & Compliance Officer Membership No.: A 24346 Enclosure: As above Sterlite Technologies Limited R egistered office: 4th Floor, Godrej Millennium, Koregaon Road 9, STS 12/1, Pune, Maharashtra- 411 001, India. CIN - L31300PN2000PLC202408 www.stl.tech PRESS RELEASE STL expands its optical connectivity portfolio in the US with the CONCAT solution Lugoff, South Carolina, 17/July/2026: STL Optical Connectivity NA, LLC, (STLOC), a U.S. subsidiary of STL (Sterlite Technologies Ltd.) [NSE: STLTECH], a leading connectivity solutions provider for AI-ready digital infrastructure, today announced that it launched its new advanced FTTH solution, CONCAT, after successfully completing field trials on the networks of one of the largest telecom service providers in the United States. Following successful field validation, CONCAT is now available to digital infrastructure providers seeking faster fiber rollouts with reduced deployment complexity and labor. It enables up to 71% in labor cost savings by eliminating most field splicing through factory-assembled, pre-connectorized fiber segments that deliver plug-and-play installation. CONCAT simplifies fiber deployment by shifting critical fiber preparation and termination into a controlled manufacturing environment ensuring consistent quality, faster installation, and lower operational risk in the field. CONCAT solution is ideal for new builds, network expansions, and overbuild programs facing aggressive broadband coverage and speed targets. By reducing installation time and field errors, CONCAT significantly improves overall project economics. The CONCAT solution features a concatenated, pre-connectorized MPO-to-LC cable assembly integrated with a versatile enclosure and cassette architecture. It supports both aerial and duct deployments. Its spliceless, modular design lets operators scale faster, add customers quicker, and cut truck rolls, rework, and labor dependency. Recently, CONCAT has also been recognised by one of the industry’s leading innovation awards based on a combination of technical merit, performance impact, design uniqueness, and overall contribution to advancing optical communications. Commenting on this development, Ryan Chappell, Vice President of Connectivity, STL, said: “The U.S. broadband market is under enormous pressure to build faster, at lower cost, and with fewer skilled labor constraints. CONCAT is engineered for this reality. By eliminating field splicing and delivering true plug-and-play, we are enabling operators to accelerate FTTx rollouts while improving quality and reducing total deployment cost - a major step forward in how fiber networks are built in America.” About STLOC – STL Optical Connectivity NA, LLC: STLOC, a U.S. subsidiary of STL, is focused on the design, manufacture, and sales of high-quality, advanced connectivity products for North American data center operators and customers. With sales and support personnel located throughout the United States, STLOC is strategically situated to enable it to effectively serve and support its growing clientele across the United States and North America. About STL STL (Sterlite Technologies Ltd.) is a global leader in advanced connectivity solutions, providing end-to-end solutions for building AI-ready infrastructure, FTTx, Rural, Enterprise and Data Center networks. Read more | Contact us | stl.tech | Twitter | LinkedIn | YouTube For more information, contact: Media Relations Investor Relations Shaily Rai Sinha Rahul Darak Phone: +1 (803)-403-2258 Phone: +91 22 30514000 stl.communications@stl.tech investor@stl.tech Sterlite Technologies Limited R egistered office: 4th Floor, Godrej Millennium, Koregaon Road 9, STS 12/1, Pune, Maharashtra- 411 001, India. CIN - L31300PN2000PLC202408