X0306 4 2015-09-02 0 0000935494 NATIONAL INSTRUMENTS CORP /DE/ NATI 0001008359 TRUCHARD JAMES J C/O NATIONAL INSTRUMENTS CORP 11500 N. MOPAC EXPRESSWAY, BLDG. C AUSTIN TX 78759-3504 1 1 1 0 President Common Stock 2015-09-02 4 J 0 300973 0 D 9063124 D Common Stock 2015-09-02 4 J 0 300973 0 A 9364097 D Common Stock 2015-09-02 4 J 0 300973 0 D 0 I Held by the Trust. Common Stock 2015-09-02 4 J 0 300973 0 A 300973 I Held by the Trust. Common Stock 3281250 I Held by Truchard NATI Partners, Ltd., Dr. Truchard is the general partner. Common Stock 300972 I Held by James J. Truchard TTEE James J. Truchard Descendants Trust II, Dr. Truchard is the trustee. Common Stock 77243 I Held by Truchard Foundation, Dr. Truchard is the president. For estate planning purposes, on September 2, 2015 (the "Transfer Date"), Dr. James J. Truchard ("Dr. Truchard") transferred, for no consideration, 300,973 shares of the issuer's common stock to the James J. Truchard TR Truchard Descendants Trusts UA 04-JUN-93 (the "Trust"). Simultaneously on the Transfer Date, the Trust transferred, for no consideration, 300,973 shares of the issuer's common stock with a different cost basis for tax purposes to Dr. Truchard. On February 22, 2011, the common stock of National Instruments Corporation split 3-for-2, resulting in the Trust's ownership of 200,648 additional shares of common stock. David G. Hugley as attorney-in-fact for James J. Truchard 2015-09-02