UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE TO

Amendment No. 6

(Rule 14d-100)

Tender Offer Statement under Section 14(d)(1) or 13(e)(1)
of the Securities Exchange Act of 1934

Herley Industries, Inc.

(Name of Subject Company (Issuer))

Lanza Acquisition Co.

and

Kratos Defense & Security Solutions, Inc.

(Name of Filing Persons (Offerors))

Common Stock, $0.10 par value
(Title of Class of Securities)

427398102
(CUSIP Number of Class of Securities)

Eric M. DeMarco
President and Chief Executive Officer
Kratos Defense & Security Solutions, Inc.
4820 Eastgate Mall

San Diego, CA 92121
(858) 812-7300
(Name, address and telephone number of person authorized
to receive notices and communications on behalf of filing persons)

Copy to:

Deyan Spiridonov

Teri O’Brien

Paul, Hastings, Janofsky & Walker LLP

4747 Executive Drive, 12th floor

San Diego, CA 92121

(858) 458-3000

CALCULATION OF FILING FEE

*              Estimated for purposes of calculating the filing fee only. This calculation assumes the purchase of 15,616,154 shares of the Common Stock of Herley Industries, Inc. (representing the number of shares, including common stock outstanding and options) at the tender offer price of $19.00 per share.

**           The amount of the filing fee, calculated in accordance with Rule 0-11 under the Securities Exchange Act of 1934, as amended, and Fee Rate Advisory #5 for fiscal year 2011, issued December 22, 2010, by multiplying the transaction value by .0001161.

x           Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

o            Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

x           third-party tender offer subject to Rule 14d-1.

o            issuer tender offer subject to Rule 13e-4.

o            going-private transaction subject to Rule 13e-3.

o            amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: x

If applicable, check the appropriate box(es) below to designate the appropriate rule provision(s) relied upon:

o            Rule 13e-4(i) (Cross-Border Issuer Tender Offer)

o            Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)

This Amendment No. 6 (this “Amendment”) amends and supplements the Tender Offer Statement on Schedule TO (together with any amendments and supplements thereto, the “Schedule TO”) originally filed with the Securities and Exchange Commission on February 25, 2011, as amended by Amendment No. 1 filed on March 8, 2011, Amendment No. 2 filed on March 15, 2011, Amendment No. 3 filed on March 17, 2011, Amendment No. 4 filed on March 25, 2011 and Amendment No. 5 filed on March 30, 2011, relating to the offer by Lanza Acquisition Co., a Delaware corporation (the “Purchaser”) and an indirect wholly-owned subsidiary of Kratos Defense & Security Solutions, Inc., a Delaware corporation (“Kratos”) to purchase all of the issued and outstanding shares of common stock, par value $0.10 per share (collectively, the “Shares” and each, a “Share”), of Herley Industries, Inc., a Delaware corporation (“Herley”) at a purchase price of $19.00 per Share, net to the seller in cash, without interest, less any applicable withholding taxes (the “Offer Price”), upon the terms and subject to the conditions set forth in the Offer to Purchase, dated February 25, 2011 (together with any amendments and supplements thereto, the “Offer to Purchase”), and in the related Letter of Transmittal (the “Letter of Transmittal”), copies of which are filed with the Schedule TO as Exhibits (a)(1)(A) and (a)(1)(B), respectively.  Capitalized terms used and not otherwise defined in this Amendment shall have the meanings assigned to such terms in the Offer to Purchase or in the Schedule TO.  This Amendment is being filed on behalf of Kratos and the Purchaser.

All the information set forth in the Offer to Purchase and Letter of Transmittal: (i) is incorporated by reference herein in response to Item 8 and Items 11 through 12 of the Schedule TO, (ii) is supplemented by the information specifically provided in this Amendment and (iii) except as otherwise set forth below, remains unchanged.  Capitalized terms used and not otherwise defined in this Amendment shall have the meanings assigned to such terms in the Offer to Purchase or in the Schedule TO.

Item 8 and Item 11

Item 8 and Item 11 of the Schedule TO are hereby amended and supplemented by adding the following text:

The subsequent offering period of the Offer expired at 12:00 midnight, New York City time, on Tuesday, March 29, 2011.  According to Wells Fargo Bank, N.A., the depositary for the Offer, as of 12:00 midnight, New York City time, March 29, 2011, a total of 13,171,564 Shares were validly tendered in the initial and subsequent offering periods of the Offer. The tendered Shares represent approximately 93.3% of all outstanding Shares.  Payment for Shares tendered during the subsequent offering period is expected to be made promptly.

The acquisition of Herley has been completed through a merger of the Purchaser with and into Herley, and Herley is now an indirect wholly-owned subsidiary of Kratos.  The merger was implemented on an expedited basis pursuant to the short-form merger procedure available under Delaware law effective March 30, 2011.

2

Item 12

Item 12 of the Schedule TO is hereby amended and supplemented as follows:

(a)(5)(E)  Press Release issued by Kratos Defense & Security Solutions, Inc. on March 30, 2011.

3

SIGNATURES

After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

4

INDEX TO EXHIBITS

* Previously Filed

5

Exhibit (a)(5)(E)

FOR IMMEDIATE RELEASE

KRATOS DEFENSE & SECURITY SOLUTIONS, INC.

COMPLETES ACQUISITION OF HERLEY INDUSTRIES

SAN DIEGO, CA, March 30, 2011—Kratos Defense & Security Solutions, Inc. (NASDAQ: KTOS), a leading National Security Solutions provider, today announced the successful completion of its acquisition of Herley Industries, Inc. (NASDAQ: HRLY) at a price of $19.00 per share.  Kratos completed the acquisition through a cash tender offer and a subsequent short-form merger of an indirect wholly owned subsidiary with and into Herley.

As a result of the merger, all outstanding shares of Herley common stock not validly tendered and accepted for payment in the tender offer were converted into the right to receive $19.00 per share in cash, without interest and less any required withholding taxes. The depositary for the tender offer will mail to non-tendering stockholders materials necessary to exchange Herley stock certificates for such payment.  As a result of the Merger, Herley shares ceased trading on the NASDAQ Global Select Market.

Eric DeMarco, President and CEO of Kratos, said, “Herley is one of the premier technology, engineering and high-tech national defense focused electronics products businesses in the industry today.  With this acquisition, Kratos gains significant expertise in numerous established electronic attack and electronic warfare platforms, tactical missile systems, and strategic deterrence systems which complement our existing business in manned and unmanned aircraft, missile systems and certain other programs.  I want to personally welcome Rich Poirier, his management team, and the Herley employees to Kratos, where together we will continue our strategy of building the premier National Security products, solutions and services business in the industry today.”

About Kratos Defense & Security Solutions

Kratos Defense & Security Solutions, Inc. (NASDAQ: KTOS) is a specialized National Security business providing mission critical products, services and solutions for United States National Security priorities. Kratos’ core capabilities are sophisticated engineering, manufacturing and system integration offerings for National Security platforms and programs. Kratos’ areas of expertise include Command, Control, Communications, Computing, Combat

Systems, Intelligence, Surveillance and Reconnaissance (C5ISR), unmanned systems, cyber warfare, cyber security, information assurance, critical infrastructure security, and weapons systems sustainment. Kratos has primarily an engineering and technical oriented work force of approximately 3,900, the majority of which hold an active National Security clearance, including Secret, Top Secret and higher. The vast majority of Kratos’ work is performed on a military base, in a secure facility, or at a critical infrastructure location. Kratos’ primary end customers are United States Federal Government agencies, including the Department of Defense, classified agencies, intelligence agencies and Homeland Security related agencies.  News and information are available at www.kratosdefense.com.

Additional Information and Where to Find It

This press release is neither an offer to purchase nor a solicitation of an offer to sell securities. Stockholders of Herley are urged to read the relevant tender offer documents and all amendments thereto because they will contain important information that stockholders should consider before making any decision regarding tendering their shares. Kratos and its acquisition subsidiary have filed a tender offer statement on Schedule TO with the SEC and Herley has filed a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer described in this press release. Any offers to purchase or solicitations of offers to sell will be made only pursuant to such tender offer statement. The tender offer statement (including an offer to purchase, a related letter of transmittal and other offer documents) and all amendments thereto and the related solicitation/recommendation statement and all amendments thereto contain important information, including the various terms of, and conditions to, the tender offer, that should be read carefully by Herley’s stockholders before they make any decision with respect to the tender offer. Such materials will be made available to Herley’s stockholders at no expense to them. In addition, such materials (and all other offer documents filed with the SEC) are available at no charge on the SEC’s Web site: www.sec.gov and may also be obtained by directing a request to the Corporate Secretary of Kratos Defense & Security Solutions, Inc., at (858) 812-7300.