ADTN · ADTRAN Holdings, Inc.

News summary: Operators face rising edge capacity demands as 100G becomes standard across access, aggregation and mobile backhaul Adtran’s new Terabit-class edge routers deliver high-capacity in compact, cabinet-ready platforms Open disaggregated architecture integrates routing, optics and software-driven management for simplicity, flexibility and control Adtran today extended its edge routing portfolio with new Terabit-class edge routers, featuring 400Gbit/s interfaces. These new devices give operators a practical, cost-effective way to scale capacity at the network edge without adding space, power or operational burden. Supported by a unified software foundation that simplifies deployment and operations across the portfolio, the solutions provide a consistent, future-ready environment for edge growth. With 100Gbit/s interfaces now widely deployed across fiber access, aggregation and mobile backhaul, operators need higher-capacity edge options that reduce cost, complexity and

News summary: Adtran will show how intelligent optical networks can scale infrastructure while controlling power, complexity and security risks Highlights include LiteWave800 ™ , an ultra‑low‑power 800G pluggable transceiver, which sets a new 1pJ/bit benchmark for intra‑data center connectivity Adtran will participate in OIF multi‑vendor interoperability demos and present European‑led innovation through advanced research projects Adtran today announced that it will showcase its latest optical innovations at OFC 2026, taking place from March 15 to 19 in Los Angeles. The company will outline how intelligent, secure and power‑efficient optical networks are shaping the next phase of AI infrastructure. Adtran’s optical networking technology is helping build the foundation for the AI era. At Adtran’s booth (1001), visitors can explore solutions spanning ultra‑low‑power intra‑data center connectivity, automated open optical transport, access evolution and AI‑enabled operations. Adtran

News summary: Live OIF demo brings together 40 companies to highlight real‑world multi‑vendor operation across open optical networks Showcase demonstrates interoperable 100G, 400G and 800G ZR+ transport over open line systems with multi-domain control Adtran’s ZR+ pluggables feature across both the OIF demo and plugfest, highlighting their role in open, multi-vendor deployments at scale Adtran today announced it’s playing a key role in the OIF’s multi-vendor interoperability demo at OFC 2026. The showcase brings together 40 member companies, highlighting real‑world operation across open optical networks. It validates multi‑vendor 100Gbit/s, 400Gbit/s and 800Gbit/s ZR+ coherent pluggable transceivers operating over open line systems. Featuring Adtran’s FSP 3000 OLS , coherent ZR+ pluggable optics and Mosaic Network Controller , the setup extends previous years’ configurations to include C‑ and L‑band operation and multi‑layer domain control. Adtran’s 800Gbit/s ZR+ pluggables also

News summary: AI clusters and GPU fabrics demand massive capacity, yet traditional 800G optics increase energy consumption, heat and cost burdens Adtran’s LiteWave800™ introduces a new class of ultra-low-power, low-latency DR8 LPO modules built on a fully re-engineered design Breakthrough energy efficiency of 1pJ/bit enables greener, scalable intra-data center links for next-generation AI and cloud workloads Adtran today launched LiteWave800™, an ultra‑low‑power 800Gbit/s DR8 linear pluggable optics (LPO) module engineered to help data centers address the power, latency, thermal and bandwidth demands of modern AI and machine-learning (ML) workloads. As GPU clusters grow and short-reach links scale across dense server racks, operators need 800Gbit/s optics that deliver higher capacity within strict power and cooling limits. LiteWave800™ answers this challenge with a fully re-engineered architecture that significantly reduces energy consumption. Operating at just 1pJ/bit and consuming

News summary: Rural electric co-op needed a scalable, easy-to-manage network with transparent pricing, real-time insights and faster troubleshooting Adtran’s fiber access, Wi-Fi and cloud management technology supports expansion into underserved areas and rapid fault resolution Solution delivers 20-30% cost savings, improved subscriber experience and greater operational efficiency Adtran today announced that Jackson County REMC is transforming its broadband network with Adtran technology to help close the digital divide and bring faster, more reliable connectivity to homes, businesses and farms across southern Indiana. The member-owned electric co-op selected Adtran for its transparent approach and collaborative partnership, moving away from restrictive models that added complexity and cost. The integrated solution combines fiber access, AI-driven Mosaic One SaaS and Intellifi ® managed Wi‑Fi to reduce truck rolls and lower operating expenses by up to 30%. This empowers Jackson County

ADTRAN Holdings, Inc. (NASDAQ: ADTN and FSE: QH9) (“ADTRAN Holdings” “ADTRAN” or the “Company”) today announced its unaudited financial results for the fourth quarter ended December 31, 2025. Revenue: $291.6 million, up 20.1% year-over-year. GAAP gross margin of 39.0%; Non-GAAP gross margin of 42.5%; up 213 and 122 basis points year-over-year, respectively. Operating margin: GAAP operating margin of 1.5%; non-GAAP operating margin of 6.4%. Net cash provided by operating activities of $42.2 million. GAAP diluted loss per share of $0.02; non-GAAP diluted earnings per share of $0.16. Cash and cash equivalents of $95.7 million. ADTRAN Holdings Chairman and Chief Executive Officer Tom Stanton stated, “We delivered a strong fourth quarter, with revenue above our outlook and growth across all three revenue categories. Performance reflected solid execution and sustained fiber investment across our core markets.” Mr. Stanton added, “As we look at 2026, we see solid momentum with cloud and