13D Filing: Discovery Group I, LLC and Planet Payment Inc (PLPM)

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)

 

UNDER THE SECURITIES
EXCHANGE ACT OF 1934

(Amendment No. )*

 

Planet
Payment, Inc.

(Name of Issuer)

 

Common Stock, par value $0.01 per share

(Title of Class of Securities)

 

U72603118

(CUSIP Number)

Discovery Group I, LLC

300 South Wacker Drive

Suite 600

Chicago, Illinois 60606

Telephone Number: (312) 265-9600

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

May 17, 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 to be sent.

^*The remainder of
this cover page shall be filled out for a reporting person’s 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).