Archrock Inc. (AROC): Carlson Capital Increase Its Stake; Plans to Go Activist

NAMES OF
REPORTING PERSON

Double Black Diamond Offshore Ltd.

CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP

(a)  ¨        (b)  x

SEC USE ONLY

SOURCE OF FUNDS

WC

CHECK BOX IF DISCLOSURE OF LEGAL
PROCEEDING IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) ¨

CITIZENSHIP OR PLACE OF
ORGANIZATION

    Cayman Islands

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH

SOLE VOTING POWER

0

SHARED VOTING POWER

5,498,738

SOLE DISPOSITIVE POWER

0

SHARED DISPOSITIVE POWER

5,498,738

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

5,498,738

CHECK IF THE AGGREGATE AMOUNT IN ROW
(11) EXCLUDES CERTAIN SHARES ¨

PERCENT OF CLASS REPRESENTED BY AMOUNT
IN ROW (11) EXCLUDES CERTAIN SHARES

7.90%

TYPE OF REPORTING PERSON

CO