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 * HELMER MAUREEN O   2. Issuer Name and Ticker or Trading Symbol PLUG POWER INC [PLUG] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) PLUG POWER INC., 968 ALBANY-SHAKER ROAD 3. Date of Earliest Transaction (Month/Day/Year) 06/01/2005 (Street) LATHAM, NY 12110 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 06/01/2005   A   3,617 A $ 6.22 3,617 D (1)   Common Stock 06/01/2005   D   3,617 D $ 6.22 0 (1) 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

Option to Purchase Common Stock

$ 6.22

06/01/2005

A(2)

10,000

06/01/2006(3)

06/01/2015

Common Stock

10,000

$ 6.22

35,000

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
HELMER MAUREEN O PLUG POWER INC. 968 ALBANY-SHAKER ROAD LATHAM, NY 12110	X

Signatures

/s/ David A. Neumann on behalf of Maureen O. Helmer		06/03/2005
**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)	Maureen O. Helmer, a director of Plug Power, Inc. and partner at Cough White LLP, has assigned to Couch White LLP, pursuant to the terms of her employment, all of her pecuniary interest in the shares issued to her under Plug Power's Non-Employee Director Compensation Plan (including the sale or transfer of such shares) and disclaims beneficial ownership therein.
(2)	Awarded pursuant to Plug Power's Non-Employee Director Compensation Plan
(3)	Consists of an option to acquire common stock granted on June 1, 2005 with respect to which: 10,000 shares, with an exercise price equal to fair market value on the date of grant, fully vest on the first anniversary of the date of the grant.

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