Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Pershing Square Capital Management, L.P.
   2. Issuer Name and Ticker or Trading Symbol
CERIDIAN CORP /DE/ [CEN] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
888 SEVENTH AVENUE, 29TH FLOOR		 3. Date of Earliest Transaction (Month/Day/Year)
02/28/2007
(Street)

NEW YORK, NY 10019		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 02/28/2007   P   808,400 A $ 32.5923 20,532,734 I See footnotes (1) (2)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Pershing Square Capital Management, L.P.
888 SEVENTH AVENUE, 29TH FLOOR
NEW YORK, NY 10019		     X    
PS Management GP, LLC
888 SEVENTH AVENUE, 29TH FLOOR
NEW YORK, NY 10019		     X    
Pershing Square GP, LLC
888 SEVENTH AVENUE, 29TH FLOOR
NEW YORK, NY 10019		     X    
ACKMAN WILLIAM A
888 SEVENTH AVENUE, 29TH FLOOR
NEW YORK, NY 10019		     X    

Signatures

 PERSHING SQUARE CAPITAL MANAGEMENT, L.P., By: PS Management GP, LLC, its General Partner, By: /s/ William A. Ackman, Managing Member   03/01/2007
**Signature of Reporting Person Date
 PS MANAGEMENT GP, LLC, By: /s/ William A. Ackman, Managing Member   03/01/2007
**Signature of Reporting Person Date
 PERSHING SQUARE GP, LLC, By: /s/ William A. Ackman, Managing Member   03/01/2007
**Signature of Reporting Person Date
 /s/ William A. Ackman   03/01/2007
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) In addition to Pershing Square Capital Management, L.P. ("PS Capital"), this Form 4 is being filed jointly by PS Management GP, LLC ("PS Management"), Pershing Square GP, LLC ("PSGP") and William A. Ackman, each of whom has the same business address as PS Capital and may be deemed to have a pecuniary interest in securities beneficially owned by the investment funds referred to herein.
(2) Represents 8,980,821 shares held for the account of Pershing Square, L.P. ("PSI"), 111,899 shares held for the account of Pershing Square II, L.P. ("PSII") and 11,440,014 shares held for the account of Pershing Square International, Ltd. ("PSIL"). Each of PSI, PSII and PSIL is an investment fund for which PS Capital acts as investment advisor and may be deemed the beneficial owner of securities beneficially owned by it. PS Management is general partner of PS Capital and may be deemed beneficial owner of securities beneficially owned by it. PSGP is general partner of PSI and PSII and may be deemed beneficial owner of securities beneficially owned by them. Mr. Ackman is the managing member of PSGP and PS Management and may be deemed beneficial owner of securities beneficially owned by them. Each of PS Capital, PS Management, PSGP and Mr. Ackman disclaims beneficial ownership of the securities reported in this Form 4 except to the extent of its or his pecuniary interest therein.

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