UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 2)*

Cartesian, Inc.

(Name of Issuer)

Common Stock, par value $0.005 per share

(Title of Class of Securities)

146534102

(CUSIP Number)

Mill Road Capital, L.P.

Attn: Thomas E. Lynch

382 Greenwich Avenue

Suite One

Greenwich, CT 06830

203-987-3500

With a copy to:

Peter M. Rosenblum, Esq.

Foley Hoag LLP

155 Seaport Blvd.

Boston, MA 02210

617-832-1151

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

November 2, 2017

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Introduction

This Amendment No. 2 to the joint statement on Schedule 13D with respect to the Common Stock, par value $0.005 per share (the “Common Stock”), of Cartesian, Inc., a Delaware corporation f/k/a The Management Network Group, Inc. (the “Issuer”), filed by Mill Road Capital, L.P., a Delaware limited partnership (the “Fund”), Mill Road Capital GP LLC, a Delaware limited liability company (the “GP”), Thomas E. Lynch and Scott P. Scharfman (collectively, the “Reporting Persons”) on August 17, 2009, as amended and restated by Amendment No. 1 on Schedule 13D with respect to the Common Stock filed by the Reporting Persons on April 7, 2014 (such joint statement, as so amended and restated and as amended herein, the “Schedule 13D”), amends the Schedule 13D as follows:

“Item 3. Source and Amount of Funds or Other Consideration

The Reporting Persons acquired beneficial ownership of an aggregate of 174,886 shares of Common Stock for $415,971.63 using working capital from the Fund and the proceeds of margin loans under margin loan facilities maintained in the ordinary course of business by the Fund with a broker on customary terms and conditions.”

“Item 5. Interest in Securities of the Issuer

(a, b) The percentages of beneficial ownership reported in this Item 5, and on each Reporting Person’s cover page to this Schedule 13D, are based on a total of 8,986,014 shares of the Common Stock issued and outstanding as of July 29, 2017, as reported in the most recent quarterly report of the Issuer on Form 10-Q for the fiscal quarter ended July 1, 2017. All of the share numbers reported below, and on each Reporting Person’s cover page to this Schedule 13D, are as of the time of filing of this Amendment No. 2. to the Schedule 13D on November 6, 2017, unless otherwise indicated. The cover page to this Schedule 13D for each Reporting Person is incorporated by reference in its entirety into this Item 5(a, b).

The Fund directly holds, and thus has sole voting and dispositive power over, 174,886 shares of Common Stock. The GP, as sole general partner of the Fund, also has sole authority to vote (or direct the vote of), and to dispose (or direct the disposal) of, these shares of Common Stock on behalf of the Fund, and each of Messrs. Lynch and Scharfman has shared authority to vote (or direct the vote of), and to dispose (or direct the disposal) of, these shares on behalf of the GP. Accordingly, each of the Reporting Persons beneficially owns 174,886 shares of Common Stock, or approximately 1.9% of the outstanding shares of Common Stock, and the Reporting Persons beneficially own, in the aggregate, 174,886 shares of Common Stock, or approximately 1.9% of the outstanding shares of Common Stock. Mr. Jacobs does not have beneficial ownership of any shares of Common Stock.

(c) No Reporting Person, other than the Fund as set forth in the table below, effected any transaction in shares of the Common Stock from September 7, 2017 (the date sixty days prior the filing of this Amendment No. 2 to the Schedule 13D) to the time of filing of this Amendment No. 2. to the Schedule 13D on November 6, 2017.

(e) On November 2, 2017, the Reporting Persons, individually and collectively, ceased to have beneficial ownership of more than 5.0% of the Common Stock.”

[signature pages follow]

Signature

After reasonable 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.