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

                                    Form 13F
                               Form 13F COVER PAGE
Report for the Calendar Year or Quarter Ended: 12/31/2011
Check here if Amendment []; Amendment Number:
                                               -------
This Amendment (Check only one.):               [] is a restatement.
                                                [] adds new holdings entries.

Institutional Investment Manager Filing this Report:


Name:      MAK Capital One LLC

Address:   590 Madison Avenue, 9th Floor
           New York, New York 10022


Form 13F File Number: 028-12344


The institutional investment manager filing this report and the person by whom
it is signed hereby represent that the person signing the report is authorized
to submit it, that all information contained herein is true, correct and
complete, and that it is understood that all required items, statements,
schedules, lists, and tables, are considered integral parts of this submission.

Persons Signing this Report on Behalf of Reporting Manager:

Name:   Michael Kaufman
Title:  Managing Member
Phone:  (212) 486-3211

Signature,  Place,  and  Date  of  Signing:

/s/ Michael Kaufman                New York, New York                 2/14/2012
---------------------------------  ---------------------------------  ----------
[Signature]                        [City, State]                      [Date]



Report  Type  (Check  only  one):

[X]     13F HOLDINGS REPORT. (Check here if all holdings of this reporting
        manager are reported in this report.)

[ ]     13F NOTICE. (Check here if no holdings reported are in this report,
        and all holdings are reported by other reporting manager(s).)

[ ]     13F COMBINATION REPORT. (Check here if a portion of the holdings for
        this reporting manager are reported in this report and a portion are
        reported by other reporting manager(s).)

List of Other Managers Reporting for this Manager:




                              Form 13F SUMMARY PAGE

Report Summary:

Number of Other Included Managers:                    1

Form 13F Information Table Entry Total:              18

Form 13F Information Table Value Total:  $      239,868
                                         --------------
                                         (In Thousands)


List of Other Included Managers:

Provide a numbered list of the name(s) and 13F file number(s) of all
institutional investment managers with respect to which this report is filed,
other than the manager filing this report.

No.   Form 13F File Number  Name

01    028-05431             Sunrise Partners Limited Partnership
----  --------------------  ----------------------------------------------------






                                                  FORM 13F INFORMATION TABLE

          COLUMN 1               COLUMN 2     COLUMN 3  COLUMN 4      COLUMN 5       COLUMN 6  COLUMN 7         COLUMN 8
---------------------------- ---------------- --------- -------- ------------------ ---------- -------- ------------------------
                                                         VALUE    SHRS OR  SH/ PUT/ INVESTMENT  OTHER       VOTING AUTHORITY
       NAME OF ISSUER         TITLE OF CLASS    CUSIP   (x$1000)  PRN AMT  PRN CALL DISCRETION MANAGERS   SOLE     SHARED   NONE
---------------------------- ---------------- --------- -------- --------- --- ---- ---------- -------- --------- --------- ----
                                                                                           
AGILYSYS INC                 COM              00847J105   42,013 5,284,648 SH       SOLE                5,284,648         0    0
AGILYSYS INC                 COM              00847J105   14,090 1,772,286 SH       DEFINED    01               0 1,772,286    0
AXCELIS TECHNOLOGIES INC     COM              054540109    3,353   463,500 SH       SOLE                  463,500         0    0
AXCELIS TECHNOLOGIES INC     COM              054540109       80    60,466 SH       DEFINED    01               0    60,466    0
CHAMPION ENTERPRISES INC     NOTE 2.750% 11/0 158496AC3        -    59,000 PRN      SOLE                   59,000         0    0
CHAMPION ENTERPRISES INC     NOTE 2.750% 11/0 158496AC3        -    25,920 PRN      DEFINED    01               0    25,920    0
EXXON MOBIL CORP             COM              30231G102   56,015   403,000 SH       SOLE                  403,000         0    0
EXXON MOBIL CORP             COM              30231G102    5,891    69,500 SH       DEFINED    01               0    69,500    0
MOSAIC CO                    COM              61945A107   28,331   561,800 SH       SOLE                  561,800         0    0
MOSAIC CO                    COM              61945A107    3,597    71,324 SH       DEFINED    01               0    71,324    0
NEUROBIOLOGICAL TECHNOLOGIES COM              64124W106      508 3,627,192 SH       SOLE                3,627,192         0    0
NEUROBIOLOGICAL TECHNOLOGIES COM              64124W106      223 1,592,865 SH       DEFINED    01               0 1,592,865    0
ORBOTECH LTD                 ORD              M75253100    2,257   226,100 SH       SOLE                  226,100         0    0
ORBOTECH LTD                 ORD              M75253100      286    28,639 SH       DEFINED    01               0    28,639    0
SIGMA DESIGNS INC            COM              826565103   11,197 1,866,160 SH       SOLE                1,866,160         0    0
SIGMA DESIGNS INC            COM              826565103    1,466   244,256 SH       DEFINED    01               0   244,256    0
ZYGO CORP                    COM              989855101   57,498 3,257,675 SH       SOLE                3,257,675         0    0
ZYGO CORP                    COM              989855101   13,064   740,183 SH       DEFINED    01               0   740,183    0