X0303 4 2011-05-01 0 0000935494 NATIONAL INSTRUMENTS CORP /DE/ NATI 0001348803 RAZDAN ASH 11500 NORTH MOPAC, BLDG C AUSTIN TX 78759 0 0 0 1 Dir Corp Dev & Ofc of Pres Common Stock 2011-05-02 4 M 0 4130 A 57050 D Common Stock 2011-05-02 4 F 0 1144 30.32 D 55906 D Common Stock 2011-05-02 5 M 0 262 23.9757 A 56168 D Restricted Stock Units 2011-05-01 4 M 0 1001 0 D 2020-05-01 Common Stock 2435 1434 D Restricted Stock Units 2011-05-01 4 M 0 1001 0 D 2021-05-01 Common Stock 3137 2136 D Restricted Stock Units 2011-05-01 4 M 0 751 0 D 2022-05-01 Common Stock 2930 2179 D Restricted Stock Units 2011-05-01 4 M 0 751 0 D 2023-05-01 Common Stock 3506 2755 D Restricted Stock Units 2011-05-01 4 M 0 626 0 D 2024-05-01 Common Stock 3375 2749 D Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock. The restricted stock units vest and become exercisable based on time and performance milestones set by the Issuer. On February 22, 2011, the common stock of National Instruments Corporation split 3-for-2, resulting in the reporting person's ownership of additional shares of common stock. David G. Hugley as attorney-in-fact for Ash Razdan 2011-05-04