X0306 4 2012-11-02 0 0000935494 NATIONAL INSTRUMENTS CORP /DE/ NATI 0001193176 ZOGAS PETER C/O NATIONAL INSTRUMENTS CORP 11500 NORTH MOPAC, BLDG B AUSTIN TX 78759 0 1 0 0 Senior Vice President Common Stock 2012-11-02 4 M 0 9264 13.4133 A 88901 D Common Stock 2012-11-02 4 S 0 9264 24.6900 D 79637 D Employee Stock Option (right to buy) 13.4133 2012-11-02 4 M 0 9264 0 D 2013-04-16 Common Stock 18000 8736 D Options vested and became exercisable based on time and performance milestones set by the Issuer. This option was previously reported as covering 8,000 shares at an exercise price of 30.18 per share, but was adjusted to reflect the 3-for-2 stock splits that occurred on February 20, 2004 and February 22, 2011. David G. Hugley as attorney-in-fact for Peter Zogas 2012-11-09