UNITED STATES
                                 SECURITIES AND EXCHANGE COMMISSION
                                              WASHINGTON, D.C. 20549


     DIVISION OF
CORPORATION FINANCE




                                                               May 21, 2020


  Via Email

  Viktor Sapezhnikov, Esq.
  Wachtell, Lipton, Rosen & Katz
  51 West 52nd Street
  New York, NY 10019

          Re:     GCP Applied Technologies Inc.
                  Definitive Additional Materials on Schedule 14A
                  Filed on May 20, 2020
                  File No. 001-37533

  Dear Mr. Sapezhnikov:

          We have reviewed the filings above and have the following comments:

      1. Please refer to the following statement: "We also believe independent
shareholders
         should be concerned with allowing Starboard and 40 North to take
creeping control of the
         Company." Please clarify what the term "creeping control" is intended
to refer to. To
         the extent that it is referring to Starboard's nominees, please
refrain from using this
         formulation in future filings. Starboard's nominees, if elected, will
owe fiduciary duties
         and otherwise be accountable to all of the Company's shareholders.
While Starboard has
         proposed six nominees for election who, if elected, would comprise a
majority of the
         Board, as a matter of law and fact, Starboard will not be obtaining
"control" of the
         Company within the meaning of the term as defined in Rule 12b-2 if its
solicitation
         succeeds.

      2. Please refer to the quoted statement in comment #1. Please either
provide support for the
         implication that Starboard and 40 North are coordinating with one
another--with respect
         to Starboard's proxy solicitation or otherwise--or refrain from making
such statement in
         future filings.


                                          *       *        *


         We remind you that the registrant and its management are responsible
for the accuracy
  and adequacy of their disclosures, notwithstanding any review, comments,
action or absence of
 Viktor Sapezhnikov, Esq.
Wachtell, Lipton, Rosen & Katz
May 21, 2020
Page | 2

action by the staff.

        Please direct any questions to Valian Afshar, Special Counsel, at (202)
551-8729, or me,
at (202) 551-3444.


                                                           Sincerely,

                                                           /s/ Perry J. Hindin

                                                           Perry J. Hindin
                                                           Special Counsel
                                                           Office of Mergers
and Acquisitions


cc:     Adam O. Emmerich, Esq.
        Gregory E. Ostling, Esq.
        Wachtell, Lipton, Rosen & Katz