X0303 4 2011-02-01 0 0000935494 NATIONAL INSTRUMENTS CORP /DE/ NATI 0001192894 ALMGREN RAY 11500 NORTH MOPAC BLDG C AUSTIN TX 78759 0 1 0 0 Vice President Common Stock 2011-02-01 4 M 0 224 29.5545 A 34845 D Common Stock 2011-02-07 4 M 0 7347 21.0417 A 42192 D Common Stock 2011-02-07 4 S 0 7347 47.1170 D 34845 D Common Stock 2011-02-07 4 S 0 14402 47.0605 D 20443 D Employee Stock Option (right to buy) 21.0417 2011-02-07 4 M 0 7347 0 D 2011-03-21 Common Stock 7653 306 D Acquisition of stock under Issuer's employee stock purchase plan. Shares were exercised under Reporting Person's 10(b)5-1 Plan. Shares were sold under Reporting Person's 10(b)5-1 Plan. Options vested and became exercisable based on time and performance milestones set by the Issuer. David G. Hugley as attorney-in-fact for Ray Almgren 2011-02-09