X0306 4 2016-02-03 0 0000929452 KNIGHT TRANSPORTATION INC KNX 0001187342 KNIGHT KEVIN P 20002 NORTH 19TH AVENUE PHOENIX AZ 85027 1 1 0 0 Executive Chairman Common Stock 2016-02-03 4 M 0 75000 18.44 A 3930300 D Common Stock 2016-02-03 4 S 0 75000 24.8293 D 3855300 I Trust Employee Stock Option (right to buy) 18.44 2016-02-03 4 M 0 75000 0 D 2010-12-31 2016-05-23 Common Stock 75000 0 D This is the exercise of derivative securities. The grant will expire within the next few months and the options are being exercised at this time to ensure the exercise is completed before the expiration date and when exercise is not restricted. This transaction was executed in multiple trades at prices ranging from $24.24 to $25.15 per share. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, Knight Transportation, Inc. or a shareholder of Knight Transportation, Inc. full information regarding the number of shares and prices at which the transaction was effected. /s/ Kevin P. Knight 2016-02-04