Description of Registered Securities

The following is a summary of the Company’s capital stock and certain provisions of its Certificate of Incorporation, as amended (the “Certificate”) and Amended and Restated Bylaws (the “Bylaws”). This summary does not purport to be complete and is qualified in its entirety by the provisions of the Certificate and the Bylaws, each of which is incorporated herein by reference and attached as an exhibit to the Company’s most recent Annual Report on Form 10-K filed with the Securities and Exchange Commission. We encourage you to read the Company’s Certificate, Bylaws and the applicable provisions of the Delaware General Corporate Law for additional information.

Shares Outstanding. The Company is authorized to issue up to 360,000,000 shares of common stock, par value $0.01 per share (the “Common Stock”).

Dividends. Subject to prior rights and preferences, if any, applicable to shares of preferred stock of the Company (“Preferred Stock”) or any series thereof, the holders of shares of Common Stock shall be entitled to receive such dividends (payable in cash, stock, or otherwise) as may be declared thereon by the Company’s Board of Directors (the “Board”) at any time and from time to time out of any funds of the Company legally available therefor. Delaware law allows a corporation to pay dividends only out of surplus, as determined under Delaware law.

Voting Rights. Each share of Common Stock is entitled to one vote on all matters submitted to a vote of stockholders. The directors of the Company are elected by a plurality of the voting power of the shares present in person or represented by proxy. On most other matters submitted to the stockholders, the affirmative vote of the majority of the voting power of the shares present in person or represented by proxy shall be the act of the shareholders, however in certain circumstances the affirmative vote of the holders of at least 80% of the votes of the outstanding shares of stock generally entitled to vote in the election of directors shall be the act of the shareholders as described below under “Supermajority Voting Requirements for Stockholders.”

Liquidation Rights. In the event of any voluntary or involuntary liquidation, dissolution or winding up of the Company, after distribution in full of the preferential amounts, if any, to be distributed to the holders of shares of the Preferred Stock or any series thereof, the holders of the Common Stock shall be entitled to receive all of the remaining assets of the Company available for distribution to its stockholders, ratably in proportion to the number of shares of the Common Stock held by them. A liquidation, dissolution, or winding-up of the Company, as such terms are used in this paragraph, shall not be deemed to be occasioned by or to include any consolidation or merger of the Company with or into any other corporation or corporations or other entity or a sale, lease, exchange or conveyance of all or a part of the assets of the Company.

Fully Paid. The issued and outstanding shares of Common Stock are fully paid and non-assessable. This means the full purchase price for the outstanding shares of Common Stock has been paid and the holders of such shares will not be assessed any additional amounts for such shares. Any additional shares of Common Stock that the Company may issue in the future will also be fully paid and non-assessable.

Other Rights. The shares of Common Stock are not subject to redemption by operation of a sinking fund or otherwise. Holders of shares of Common Stock are not currently entitled to pre-emptive rights or conversion rights or other subscription rights.

Transfer Agent and Registrar. The transfer agent and registrar for the Common Stock is Computershare Trust Company, N.A.

Listing. Our Common Stock is listed on the NASDAQ Stock Market, LLC under the trading symbol “NATI”.

All rights under the Preferred Stock Rights Agreement expired on May 10, 2014 and as of such time, no rights had been exercised.

Some provisions of Delaware law, the Certificate and Bylaws could make the following more difficult:

a.acquisition of the Company by means of a tender offer,

b.acquisition of the Company by means of a proxy contest or otherwise, or

c.removal of the Company’s incumbent officers and directors.

These provisions, summarized below, are expected to discourage and prevent coercive takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire control of the Company to first negotiate with the Board. They are also intended to provide our management with the flexibility to enhance the likelihood of continuity and stability if our Board determines that a takeover is not in our best interests or the best interests of the stockholders. These provisions, however could have the effect of discouraging attempts to acquire us, which could deprive our stockholders of opportunities to sell their shares of Common Stock at prices higher than prevailing market prices. The Company believes that the benefits of these provisions, including increased protection, give it the potential ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure the Company and outweigh the disadvantages of discouraging takeover proposals, because negotiation of takeover proposals could result in an improvement of their terms.

Size of Board and Vacancies. The Bylaws provide that the Board will have three or more members, not to exceed twelve members, which number will be determined from time to time by resolution of the Board. Our Certificate provides for a classified Board consisting of three classes of directors, each serving a staggered three-year term. The Certificate and Bylaws contain provisions that establish specific procedures for appointing and removing members of the Board. Under the Certificate and the Bylaws, vacancies and newly created directorships on the Board may be filled only by a majority of directors then serving on the Board. Under the Certificate and Bylaws, directors may be removed at any time, but only by the affirmative vote of the holders of at least 80% of the votes of the outstanding shares of stock generally entitled to vote in the election of directors.

Elimination of Stockholder Action by Written Consent. The Bylaws eliminate the right of the Company’s stockholders to act by written consent. Stockholder action must take place at the annual or a special meeting of the Company’s stockholders.

Stockholder Meetings. Under the Bylaws, only the chairperson of the Board, the Chief Executive Officer or the majority of the authorized number of directors on the Board may call special meetings of the Company’s stockholders.

Requirements for Advance Notification of Stockholder Nominations and Proposals. The Bylaws establish advance notice procedures and information requirements with respect to stockholder proposals and nomination of candidates for election as directors.

Delaware Anti-takeover Law. The Company is subject to Section 203 of the Delaware General Corporation Law (“Section 203”), an anti-takeover law. In general, Section 203 prohibits a publicly held Delaware corporation from engaging in a business combination with an interested stockholder for a period of three years following the date such person became an interested stockholder, unless the business combination or the transaction in which such person became an interested stockholder is approved in a prescribed manner. Generally, a “business combination” includes a merger, asset or stock sale, or other transaction resulting in a financial benefit to the interested stockholder. Generally, an “interested stockholder” is a person that, together with affiliates and associates, owns, or within three years prior to the determination of interested stockholder status did own, 15% or more of a corporation’s voting stock. The existence of this provision may have an anti-takeover effect with respect to transactions not approved in advance by the Board, including discouraging attempts that might result in a premium over the market price for the shares of Common Stock held by stockholders.

No Cumulative Voting. Neither the Certificate nor Bylaws provide for cumulative voting in the election of directors.

Undesignated Preferred Stock. The authorization of the Company’s undesignated Preferred Stock makes it possible for the Board to issue Preferred Stock with voting or other rights or preferences that could impede the success of any attempt to change control of the Company.

Supermajority Voting Requirements for Stockholders. The Company’s Certificate and Bylaws require the affirmative vote of the holders of at least 80% of the votes of the outstanding shares of stock generally entitled to vote in the election of directors for the removal of a director, the approval of a business combination (as defined in the Certificate), the amendment, repeal or modification of the Bylaws and the amendment, repeal or modification of certain provisions of the Certificate, including, among other things, relating to the elimination of stockholder action by written consent, business combinations and the absence of preemptive rights of stockholders.