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 *
YORK DOUGLAS W
  2. Issuer Name and Ticker or Trading Symbol
ST MARY LAND & EXPLORATION CO [SM]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Exec. VP & COO
(Last)
(First)
(Middle)
1776 LINCOLN ST, STE 700
3. Date of Earliest Transaction (Month/Day/Year)
05/19/2005
(Street)

DENVER, CO 80202
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ 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; $.01 Par Value 05/19/2005   M   5,828 A $ 16.6562 18,324 D  
Common Stock; $.01 Par Value 05/19/2005   S   5,828 (1) D $ 25 12,496 D  
Common Stock; $.01 Par Value 05/19/2005   M   11,436 A $ 7.965 23,932 D  
Common Stock; $.01 par Value 05/19/2005   S   11,436 (2) D $ 25 12,496 D  
Common Stock; $.01 Par Value 05/19/2005   M   11,436 A $ 10.595 23,932 D  
Common Stock; $.01 Par Value 05/19/2005   S   11,436 (3) D $ 25 12,496 D  

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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
Stock Option (Right-To-Buy) $ 16.6562 05/19/2005   M     5,828 12/31/2000 12/31/2010 Common Stock 5,828 $ 0 0 D  
Stock Option (Right-To-Buy) $ 7.96 05/19/2005   M     11,436 09/30/2001 09/30/2011 Common Stock 11,436 $ 0 0 D  
Stock Option (Right-To-Buy) $ 10.595 05/19/2005   M     11,436 12/31/2001 12/31/2011 Common Stock 11,436 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
YORK DOUGLAS W
1776 LINCOLN ST
STE 700
DENVER, CO 80202
      Exec. VP & COO  

Signatures

 Brenda L Schohn ( Attorney-In-Fact)   05/23/2005
**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) This sales reported in this Form 4 were affected pursuant to a Rule 10b-1 sales plan adopted by the reporting person on May 16, 2005
(2) This sales reported in this Form 4 were affected pursuant to a Rule 10b-1 sales plan adopted by the reporting person on May 16, 2005
(3) This sales reported in this Form 4 were affected pursuant to a Rule 10b-1 sales plan adopted by the reporting person on May 16, 2005

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