Sterlite Technologies Limited. — Capital/Financing Update 2026

Jan 22, 2026

www.stl.tech

==> picture [79 x 31] intentionally omitted <==

January 22, 2026

National Stock Exchange of India Limited

Exchange Plaza, 5[th] Floor, Plot No. C-1, G Block, Bandra Kurla Complex, Bandra (East) Mumbai – 4000517

BSE Limited

Phirozee Jeejeebhoy Towers, Dalal Street, Mumbai – 400001

Scrip ID – STLTECH

Scrip Code - 532374

Sub: - Press Release – STL announces collaboration with Colt Technology Services (Colt) for the Multi-Core Fibre (MCF) trials executed across Colt’s London metro optical network in London, UK

Dear Sir/Madam,

Sterlite Technologies Limited (‘STL’) today announces the successful collaboration with Colt Technology Services (Colt) for the Multi-Core Fibre (MCF) trials executed across Colt’s London metro optical network in London, UK which marks a significant milestone in real-world validation of MCF technology as a sustainable, high-capacity, cost-efficient backbone for next-generation networks supporting AI, cloud, and digital services.

A copy of press release in this regard is enclosed herewith.

Kindly take the above on record.

Thanking you.

Yours faithfully,

For Sterlite Technologies Limited

Digitally signed by MRUNAL MRUNAL ASAWADEKAR ASAWADEKAR Date: 2026.01.22 17:57:42 +05'30'

Mrunal Asawadekar

Company Secretary (ACS 24346)

Enclosure: As above

Sterlite Technologies Limited Registered office: 4th Floor, Godrej Millennium, Koregaon Road 9, STS 12/1, Pune, Maharashtra- 411 001, India. CIN - L31300PN2000PLC202408

www.stl.tech

==> picture [79 x 31] intentionally omitted <==

PRESS RELEASE

STL completes successful trial of Multi-Core Fibre (MCF) with Colt in the UK, powering next-gen optical connectivity

London, 22/January/2026: STL [NSE: STLTECH], a leading connectivity solutions provider for AI-ready digital infrastructure, today announced the successful collaboration with Colt Technology Services (Colt) for the Multi-Core Fibre (MCF) trials executed across Colt’s London metro optical network in London, UK. This marks a significant milestone in real-world validation of MCF technology as a sustainable, high-capacity, cost-efficient backbone for next-generation networks supporting AI, cloud, and digital services.

During the trial, STL’s Multiverse™ Multi-Core 4-core Fibre —built in the same cladding diameter as standard singlemode fibre (SMF)—was deployed. The trial was conducted within the London Metro network between two Colt PoPs, covering distances of ~ 9 km and 63 km. An 800 Gbps line rate was achieved with validation performed for 100GE and 400GE services. Comprehensive testing was carried out, including Chromatic Dispersion (CD), Polarization Mode Dispersion (PMD), Crosstalk, Throughput, Fault analysis, OTDR, Loss, and Optical Return Loss (ORL) measurements, all of which delivered satisfactory results.

STL’s MCF packs 4-cores into the same cladding diameter as standard single-mode fibre (SMF), keeping coating size at 250/200 micrometres and achieving ultra-high transmission capacity per fibre within the same diameter.

STL is among the first companies globally to take MCF from lab to real-world environments, spanning underground and duct networks with a complete ecosystem of fibres, cables, and termination solutions.

Buddy Bayer, Chief Operating Officer, Colt Technology Services , said: “As demand for network capacity surges, customers need more bandwidth without compromising security, performance, or sustainability. At Colt, we’re pushing the boundaries of optical networking, and this pilot marks a breakthrough across Europe and the USA. It demonstrates our commitment to delivering future-ready, sustainable networks that meet growing needs without costing the earth.”

“Partnerships like these exemplify how collaborative innovation can accelerate the evolution of optical infrastructure,” added Dr Badri Gomatam. CTO, STL “STL’s Multiverse MCF portfolio is engineered to meet the high-density, ultra-low latency, and resilient connectivity demands of AI, hyperscale cloud, and next-generation digital ecosystems worldwide.”

About STL - Sterlite Technologies Ltd:

STL is a global leader in advanced connectivity solutions, providing end-to-end solutions for building AI-ready infrastructure, FTTx, Rural, Enterprise and Data Centre networks. With manufacturing facilities in North America, Europe and Asia, we deliver our solutions in more than 100 countries. Data Centre & Cloud companies, Telecom operators, Internet service providers and large enterprises collaborate with STL to build their future-ready digital infrastructure. STL’s business goals are driven by customer-centricity, R&D and sustainability. Read more, Contact us, stl.tech | Twitter | LinkedIn| YouTube

For more information, contact:

	Media Relations Shaily Rai Sinha Phone: +91 22 30450450 stl.communications@stl.tech		Investor Relations Rahul Darak Phone: +91 22 30514000 investor@stl.tech

Sterlite Technologies Limited Registered office: 4th Floor, Godrej Millennium, Koregaon Road 9, STS 12/1, Pune, Maharashtra- 411 001, India. CIN - L31300PN2000PLC202408