X0306 4 2019-02-01 0 0000935494 NATIONAL INSTRUMENTS CORP NATI 0001192890 DAVERN ALEXANDER M C/O NATIONAL INSTRUMENTS CORP 11500 NORTH MOPAC AUSTIN TX 78759 1 1 0 0 Chief Executive Officer Common Stock 2019-02-01 5 M 0 482 37.5870 A 198818 D Common Stock 2019-02-01 4 A 0 53000 0 A 251818 D Performance-Based Restricted Stock Units 2019-02-01 4 A 0 53000 0 A 2034-05-01 Common Stock 53000 53000 D Acquisition of stock under Issuer's employee stock purchase plan. The number of performance-based restricted stock units ("PRSUs") reported in Table II represents the target number of PRSUs that were granted to the reporting person pursuant to the Issuer's 2015 Equity Incentive Plan. Per the terms of the award agreement governing the PRSUs, the number of underlying shares of the Issuer's common stock that the reporting person is ultimately entitled to receive at the time of vesting ranges from 0% to 200% of the target number of PRSUs granted, subject to how the Issuer's total shareholder return ranks in comparison to companies that comprise the Russell 2000 Index over a performance period consisting of the three years ended December 31, 2021. R. Eddie Dixon, Jr. as attorney-in-fact for Alexander M. Davern 2019-02-04