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Charter Amendment Approved at ADTRAN Holdings, Inc. Annual Meeting
Reports First Quarter 2026 Financial Results
Amendment to Thomas Stanton’s Employment Agreement at ADTRAN Holdings
Annual Report to Security Holders
Reports Fourth Quarter and Full Year 2025 Financial Results
Preliminary Revenue Above Guidance and Non-GAAP Earnings Per Share Above Analyst Consensus for Q4 2025
Amendment to Christoph Glingener's Employment Agreement; Salary Increased to ...
Reports Third Quarter 2025 Financial Results
Q1
FY 2024
Q3
Q2
Amended Annual Report
Notice of Late Filing for Quarterly Report
Effectiveness Notice
Registration Statement for Securities Offered under a Shelf Registration
Registration Statement for Securities to be Offered to Employees
S-3ASR
Notice of Suspension of Duty to File Reports
Additional Proxy Materials
Definitive Proxy Statement
PRE 14A
Notice of Proposed Sale of Securities
Statement of Changes in Beneficial Ownership
Schedule 13G - Ownership Report
Amended Schedule 13G - Ownership Report
Specialized Disclosure Report
Definitive Revised Proxy Statement