NCM: Served as Co-Manager for ADTRAN Holdings, Inc.’s $201.3 Million Convertible Notes Offering September 23, 2025 Northland Capital Markets served as Co-Manager for ADTRAN Holdings, Inc.’s $201.3 Million Convertible Notes Offering. Northland Capital Markets’ Investment Banking group serves corporate clients by providing the financing services they need, with the experience and commitment to get the results they seek.