X0306 4/A 2018-11-09 2018-11-16 0000926282 ADTRAN INC ADTN 0001300513 Foliano Michael 901 EXPLORER BLVD. HUNTSVILLE AL 35806 0 1 0 0 Sr VP, Global Operations Common Stock 2018-11-09 4 A 0 6958 0 A 11641 D Represents a grant of restricted stock units that vest in four equal and annual installments beginning on the first anniversary date of the grant. The reporting person is filing this amendment to correct the number of shares of Common Stock acquired on November 9, 2018. The reporting person previously reported the acquisition on November 9, 2018 of 7,130 shares of Common Stock as reported on a Form 4 filed on November 16, 2018. The actual number of shares of Common Stock acquired on November 9, 2018 was 6,958. /s/ Roger Shannon, by power of attorney 2018-11-21