13D Filing: Clearlake Capital Partners and Tangoe Inc (TNGO)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

(Rule 13d-101)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO § 240.13D-1(A) AND AMENDMENTS THERETO FILED

PURSUANT TO § 240.13D-2(A)

(Amendment No. 5)

Tangoe, Inc.

(Name of Issuer)

Common Stock, $0.0001 par value

(Title of Class of Securities)

87582Y108

(CUSIP Number)

Behdad Eghbali Clearlake Capital Partners IV Finance, L.P. c/o Clearlake Capital Group, L.P. 233 Wilshire Blvd, Suite 800 Santa Monica, California 90401 (310) 400-8800		copies to: Mehdi Khodadad Cooley LLP 3175 Hanover Street Palo Alto, California 94304 (650) 843-5000

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

April 13, 2016

(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 which is the subject of this Schedule 13D, and is filing this schedule because of Sections 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 Section 240.13d-7 for
other parties to whom copies are to be sent.

The remainder of this cover page shall be filled out for a reporting persons initial filing on this form with respect to the subject
class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

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).