ADTRAN Holdings, Inc. INVESTOR ALERT: Kirby McInerney LLP Announces Investigation Into Potential Securities Fraud

The law firm of Kirby McInerney LLP is investigating potential claims against ADTRAN Holdings, Inc. (“ADTRAN” or the “Company”) (NASDAQ: ADTN). The investigation concerns whether the Company and/or members of its senior management may have violated federal securities laws or engaged in other unlawful business practices.

On July 22, 2026, ADTRAN announced preliminary Q2 2026 revenue of $280 million to $282 million and non-GAAP operating margin of about 3.5% to 4.0%, below the Company’s prior guidance of $283 million to $303 million in revenue and non-GAAP operating margin of 5% to 9%.

In ADTRAN’s press release announcing preliminary results, Tom Stanton, Chairman and CEO, said “Our preliminary second quarter results were directly impacted by a project delay from a single customer. In addition, margins reflected the current elevated component and freight cost environment.”

On ADTRAN’s Q1 2026 call, CFO Timothy Santo had stated, “We expect revenue to be between $283 million and $303 million, and non-GAAP operating margin within a range of 5% to 9%.”

The preliminary Q2 revenue was $1 million to $23 million below the guidance, and the non-GAAP operating margin was at least 100 basis points below the guidance. Additionally, an investor presentation attached to a May 5, 2026 Form 8-K reported revenue of $286.1 million, up 15.5% year-over-year and within prior guidance of $275 million to $295 million.

The preliminary Q2 2026 revenue of $280 million to $282 million was approximately $4.1 million to $6.1 million below analyst consensus estimate.

On this news, ADTRAN stock declined by $1.69 per share, or approximately 14%, to close at $10.45 per share on July 22, 2026.

At this stage, no lawsuit has been filed. The investigation is ongoing to determine whether claims may be brought under federal securities laws.

If you purchased or otherwise acquired ADTRAN securities, have information, or would like to learn more about this investigation, please contact Lauren Molinaro of Kirby McInerney LLP by email at [email protected] , or fill out the contact form below, to discuss your rights or interests with respect to these matters at no cost.