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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¨ Preliminary Proxy Statement

¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

¨ Definitive Proxy Statement

ý Definitive Additional Materials

¨ Soliciting Material Pursuant to §240.14a-12

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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*** Exercise Your Right to Vote ***

Important Notice Regarding the Availability of Proxy Materials for the

Shareholder Meeting to Be Held on May 22, 2015

MAXWELL TECHNOLOGIES, INC.	Meeting Information
	Meeting Type:  Annual Meeting
	For holders as of:  March 23, 2015
	Date:  May 22, 2015   Time:  11:00 AM PDT
	Location:  Courtyard Marriott Hotel
	8651 Spectrum Center Boulevard
	San Diego, California 92123

	You are receiving this communication because you hold shares in the above named company.
MAXWELL TECHNOLOGIES, INC.
3888 Calle Fortunada	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).
San Diego, CA 92123
	We encourage you to access and review all of the important information contained in the proxy materials before voting.
	See the reverse side of this notice to obtain proxy materials and voting instructions.

— Before You Vote —

How to Access the Proxy Materials

Proxy Materials Available to VIEW or RECEIVE:

1. Notice & Proxy Statement 2. Form 10-K

How to View Online:

Have the information that is printed in the box marked by the arrow  (located on the following page) and visit: www.proxyvote.com.

How to Request and Receive a PAPER or E-MAIL Copy:

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— 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 information that is printed in the box marked by the arrow  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.

Voting items

The Board of Directors recommends you vote

FOR the following:

1 Election of Directors

Nominees

01 Franz Fink        02   Roger Howsman

The Board of Directors recommends you vote FOR proposals 2, 3 and 4.

2 Ratification of the appointment of BDO USA LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2015.

3 To approve an increase in the number of shares of Common Stock reserved for issuance under the 2013 Omnibus Equity Incentive Plan by 1,500,000.

4 To approve, on an advisory basis, our named executive officer compensation.

NOTE: Such other business as may properly come before the meeting or any adjournment thereof.