ATLANTA, GA — (Globe Newswire – July 27, 2026) — Holzer & Holzer, LLC is investigating whether ADTRAN Holdings, Inc. (“ADTRAN” or the “Company”) (NASDAQ: ADTN) complied with federal securities laws. On July 22, 2026, ADTRAN announced certain preliminary second quarter 2026 results, including revenue and operating margin, which both are expected to come in below the Company’s previously announced guidance range. The CEO said the preliminary second quarter results were “directly impacted by a project delay from a single customer,” and that “margins reflected the current elevated component and freight cost environment.” The price of the Company’s stock dropped following this news.

If you purchased ADTRAN stock and suffered a loss on that investment, you are encouraged to contact Corey D. Holzer, Esq. at cholzer@holzerlaw.com or Joshua Karr, Esq. at jkarr@holzerlaw.com, call our toll-free number at (888) 508-6832, or visit our website at www.holzerlaw.com/case/adtran-holdings/ to discuss your legal rights.