FORM 3
        
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

OMB APPROVAL
OMB Number: 3235-0104
Estimated average burden
hours per response...
0.5
                      
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
                      

1. Name and Address of Reporting Person *

MARXE AUSTIN W & GREENHOUSE DAVID M

2. Date of Event Requiring Statement (MM/DD/YYYY)
3/23/2012 

3. Issuer Name and Ticker or Trading Symbol

PLUG POWER INC [PLUG]

(Last)        (First)        (Middle)

C/O SPECIAL SITUATIONS FUNDS, 527 MADISON AVENUE, SUITE 2600

4. Relationship of Reporting Person(s) to Issuer (Check all applicable)

_____ Director                            ___ X ___ 10% Owner
_____ Officer (give title below)          _____ Other (specify below)

(Street)

NEW YORK, NY 10022       

(City)              (State)              (Zip)
5. If Amendment, Date Original Filed (MM/DD/YYYY)

 

6. Individual or Joint/Group Filing (Check Applicable Line)

_ X _ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person


Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock   8511620   (1) I   (1) By Limited Partnership   (1)

Table II - Derivative Securities Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(MM/DD/YYYY)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Warrant   5/25/2011   5/31/2016   Common Stock   2801762   (2) (3) $2.27   I   (2) (3) By Limited Partnerships   (2) (3)

Explanation of Responses:
( 1)  This is a joint filing by Austin W. Marxe (Marxe) and David M. Greenhouse (Greenhouse). They share voting and investment control over all securities owned by Special Situations Fund III QP, L.P. (SSFQP), Special Situations Cayman Fund, L.P. (Cayman), Special Situations Private Equity Fund, L.P. (PE), Special Situations Technology Fund, L.P. (Tech) and Special Situations Technology Fund II, L.P. (Tech2). 3,158,900 shares of Common Stock are held by SSFQP, 950,000 shares of Common Stock are held by Cayman, 581,385 shares of Common Stock are held by PE, 530,942 shares of Common Stock are held by Tech and 3,290,393 shares of Common Stock are held by Tech2. The interest of Marxe and Greenhouse in the shares of Common Stock owned by SSFQP, Cayman, PE, Tech and Tech2 is limited to the extent of his pecuniary interest.
( 2)  This is a joint filing by Austin W. Marxe (Marxe) and David M. Greenhouse (Greenhouse). They share voting and investment control over all securities owned by, Special Situations Private Equity Fund, LP (PE), Special Situations Technology Fund, L.P. (Tech) and Special Situations Technology Fund II, L.P. (Tech2). 419,145 Warrants are owned by PE, 231,239 Warrants are owned by Tech and 1,469,616 Warrants are owned by Tech2. The interest of Marxe and Greenhouse in the shares of Warrants owned by PE, Tech and Tech2 are limited to the extent of his pecuniary interest.
( 3)  The warrant may be exercised to the extent that the total number of shares of Common Stock then beneficially owned does not exceed 4.99% of the outstanding shares. The Holder may request an increase up to 9.99% of the outstanding shares, effective on the 61st day after notice is given to the Company.

Reporting Owners
Reporting Owner Name / Address
Relationships
Director 10% Owner Officer Other
MARXE AUSTIN W & GREENHOUSE DAVID M
C/O SPECIAL SITUATIONS FUNDS
527 MADISON AVENUE, SUITE 2600
NEW YORK, NY 10022

X


Signatures
Austin W. Marxe 4/2/2012
** Signature of Reporting Person Date

David M. Greenhouse 4/2/2012
** Signature of Reporting Person Date


Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5(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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.
Grafico Azioni Plug Power (NASDAQ:PLUG)
Storico
Da Giu 2024 a Lug 2024 Clicca qui per i Grafici di Plug Power
Grafico Azioni Plug Power (NASDAQ:PLUG)
Storico
Da Lug 2023 a Lug 2024 Clicca qui per i Grafici di Plug Power