UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934

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Maxwell Technologies, Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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You are receiving this communication because you hold shares in the above named company. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. *** Exercise Your Right to Vote *** IMPORTANT NOTICE Regarding the Availability of Proxy Materials See the reverse side of this notice to obtain proxy materials and voting instructions. Meeting Information Meeting Type: For holders as of: Date: Time: Location: 0000052255_1 R2.09.05.010 MAXWELL TECHNOLOGIES, INC. MAXWELL TECHNOLOGIES, INC. Kevin S. Royal 9244 BALBOA AVENUE, SAN DIEGO, CA 92123 Annual Meeting March 12, 2010 May 06, 2010 11:00 AM PDT Courtyard Marriott Hotel 8651 Spectrum Center Boulevard San Diego, California 92123

How To Vote Please Choose One of The Following Voting Methods Vote In Person: Many shareholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the Meeting you will need to request a ballot to vote these shares. Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the 12 Digit Control Number available and follow the instructions. Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card. Before You Vote How to Access the Proxy Materials Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. To facilitate timely delivery please make the request as instructed above on or before Proxy Materials Available to VIEW or RECEIVE: How to View Online: Have the 12-Digit Control Number available (located on the following page) and visit: www.proxyvote.com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET: www.proxyvote.com 2) BY TELEPHONE: 1-800-579-1639 3) BY E-MAIL*: sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the 12-Digit Control Number (located on the following page) in the subject line. 0000052255_2 R2.09.05.010 1. Notice & Proxy Statement 2. Form 10-K Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before April 21, 2010 to facilitate timely delivery.

Voting items 0000052255_3 R2.09.05.010 The Board of Directors recommends that you vote FOR the following: 1. Election of Directors Nominees 01 Mark Rossi 02 Jean Lavigne 03 Burkhard Göeschel The Board of Directors recommends you vote FOR the following proposal(s): 2 Approve an increase in the number of shares of Common Stock reserved for issuance under the 2005 Omnibus Equity Incentive Plan from 1,750,000 shares to 2,750,000 shares and approve for federal tax purposes the performance goals that may be used with respect to certain performance-based awards granted under the plan. 3 Ratification of the appointment of McGladrey & Pullen, LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2010. NOTE: Such other business as may properly come before the meeting or any adjournment thereof.

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