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

SCHEDULE 13D/A

Under the Securities Exchange Act of 1934
(Amendment No. ________)*


PLUG POWER INC

(Name of Issuer)


Common Stock, no par value
(Title of Class of Securities)


72919P202
(CUSIP Number)


Interinvest Corporation
192 South Street, Suite 600
Boston, MA 02111
Attention: Stanley T. Schmidt
Telephone: (617-723-7870)
 Name, Address and Telephone Number of Person Authorized to
Receive Notices and Communications)


October 2, 2012

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to
report the acquisition that is the subject of this Schedule 13D, and is
filing this schedule because of 240.13d-1(e), 240.13d-1(f) or 240.13d-
1(g), check the following box.

Note: Schedules filed in paper format shall include a signed original and
five copies of the schedule, including all exhibits. See Rule.13d-7 for
other parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of
that section of the Act but shall be subject to all other provisions of
the Act (however, see the Notes).





1.  Names of Reporting Persons.

 Interinvest Corporation Inc.


2.  Check the Appropriate Box if a Member of a Group (See Instructions)
(a)
(b) x

3.  SEC Use Only
4.	Source of Funds (See Instructions)

OO

5.  Check if Disclosure of Legal Proceedings Is Required Pursuant to
Items 2(d) or 2(e)

6.  Citizenship or Place of Organization

Massachusetts

   Number of
Shares

Beneficially
   Owned by
   Each
Reporting
   Person
With:
7.  Sole Voting Power                       0


8.  Shared Voting Power                     2,664,345


9.  Sole Dispositive Power                  0


10.  Shared Dispositive Power               2,664,345

11.  Aggregate Amount Beneficially Owned by Each Reporting Person
     2,664,345

12.  Check if the Aggregate Amount in Row (11) Excludes Certain Shares
(See Instructions)

13.  Percent of Class Represented by Amount in Row (11)            7.04%

14.  Type of Reporting Person (See Instructions)    IA







1.  Names of Reporting Persons.

Interinvest Consulting Corporation of Canada Limited

2.  Check the Appropriate Box if a Member of a Group (See Instructions)
(a)
(b) x

3.  SEC Use Only
4.	Source of Funds (See Instructions)

OO

5.  Check if Disclosure of Legal Proceedings Is Required Pursuant to
Items 2(d) or 2(e)
?
6.  Citizenship or Place of Organization

Canada

   Number of
Shares

Beneficially
   Owned by
   Each
Reporting
   Person
With:
7.  Sole Voting Power                       0


8.  Shared Voting Power                     1,500


9.  Sole Dispositive Power                  0


10.  Shared Dispositive Power               1,500

11.  Aggregate Amount Beneficially Owned by Each Reporting Person
1,500

12.  Check if the Aggregate Amount in Row (11) Excludes Certain Shares
(See Instructions)

13.  Percent of Class Represented by Amount in Row (11)            0.00%

14.  Type of Reporting Person (See Instructions)    IA











1.  Names of Reporting Persons.

Interinvest (Bermuda) Ltd.

2.  Check the Appropriate Box if a Member of a Group (See Instructions)
(a)
(b) x

3.  SEC Use Only
4.	Source of Funds (See Instructions)

OO

5.  Check if Disclosure of Legal Proceedings Is Required Pursuant to
Items 2(d) or 2(e)

6.  Citizenship or Place of Organization

Bermuda

   Number of
Shares

Beneficially
   Owned by
   Each
Reporting
   Person
With:
7.  Sole Voting Power                      0


8.  Shared Voting Power                    404,000


9.  Sole Dispositive Power                 0


10.  Shared Dispositive Power              404,000

11.  Aggregate Amount Beneficially Owned by Each Reporting Person
   404,000

12.  Check if the Aggregate Amount in Row (11) Excludes Certain Shares
(See Instructions)
?
13.  Percent of Class Represented by Amount in Row (11)            1.07%

14.  Type of Reporting Person (See Instructions)    IA












1.  Names of Reporting Persons.

Hans P. Black

2.  Check the Appropriate Box if a Member of a Group (See Instructions)
(a)
(b) x

3.  SEC Use Only
4.	Source of Funds (See Instructions)

OO

5.  Check if Disclosure of Legal Proceedings Is Required Pursuant to
Items 2(d) or 2(e)

6.  Citizenship or Place of Organization

Canada

   Number of
Shares

Beneficially
   Owned by
   Each
Reporting
   Person
With:
7.  Sole Voting Power                      46,000


8.  Shared Voting Power                    3,069,845


9.  Sole Dispositive Power                 46,000


10.  Shared Dispositive Power         3,069,845


11.  Aggregate Amount Beneficially Owned by Each Reporting Person
3,115,845

12.  Check if the Aggregate Amount in Row (11) Excludes Certain Shares
(See Instructions)
?
13.  Percent of Class Represented by Amount in Row (11)          8.23%

14.  Type of Reporting Person (See Instructions)   IN




ITEM 1. SECURITY AND ISSUER

This statement relates to the Common Stock, no par value (the "Common
Stock"), of Plug Power Inc. (the "Issuer") with principal
executive offices located at 968 Albany Shaker Road, Latham, NY 12110.


ITEM 2. IDENTITY AND BACKGROUND

(a)	The names of the persons filing this Schedule 13D are
Interinvest Corporation Inc., a Massachusetts corporation;
Interinvest (Bermuda) Ltd., a Bermuda corporation;
Interinvest Consulting Corporation of Canada Limited, a
Canadian corporation; and Hans P. Black, a citizen of
Canada. The foregoing persons are hereinafter sometimes
referred to collectively as the "Reporting Persons".
(b)	The principal business address of Interinvest Corporation
Inc. is 192 South Street, Suite 600, Boston, MA 02111. The
principal business address of Interinvest (Bermuda) Ltd. is
The LOM Bldg, 27 Reid Street, Hamilton HM 11, Bermuda. The principal
business address of Interinvest Consulting Corporation of
Canada Limited is 3655 rue Redpath, Montreal, QC H3G 2W8.
The principal business address of Hans P. Black is 3655 rue
Redpath, Montreal, QC H3G 2W8.
(c)	The principal business of the Reporting Persons is the
furnishing of investment advisory services. The principal
occupation of Hans P. Black is serving as Chairman of
Interinvest Consulting Corporation of Canada Limited.
(d)	During the last five years, none of the foregoing entities
have been convicted in a criminal proceeding.
(e)	During the last five years, none of the foregoing entities
have been subject  to a civil proceeding of the type
specified in Items 2(d) or (e) of Schedule 13D.
(f) Hans P. Black, a reporting person, is a citizen of Canada.


ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION

Since reporting in a SC 13D/A filing dated May 3, 2012, the
Reporting Persons have acquired an additional net quantity of
357,825 shares of Common Stock of the Issuer for an aggregate
purchase price of approximately $357,825 or $0.915/share. The
effect of these purchases has been to increase the Reporting
Persons' holdings of Common Stock of the Issuer from 7.21% to
8.23%. The source of funds for such transactions was derived
from investment advisory client accounts.


ITEM 4. PURPOSE OF TRANSACTION

The Reporting Persons acquired the Common Stock of the Issuer for
investment purposes.  The Reporting Persons have had, and from time to
time may continue to have discussions with management, other
shareholders, and third parties regarding matters relating to the
financial condition, strategy, business, assets, operations, capital
structure and strategic plans of the Issuer.

The Reporting Persons intend to review their investment in the Issuer on
a continuing basis. Depending on various factors, including the Issuer's
financial position and strategic direction, the outcome of the
discussions referenced above, actions taken by the Board of Directors of
the Issuer, price levels of the securities of the Issuer, other
investment opportunities available to the Reporting Persons, conditions
in the capital markets and general economic and industry conditions, the
Reporting Persons may in the future take such actions with respect to
their investments in the Issuer as they deem appropriate, including
purchasing additional securities of the Issuer, selling some or all of
the Reporting Persons' respective holdings in the Issuer and/or otherwise
changing their intention with respect to any and all matters referred to
in Item 4 of Schedule 13D.

ITEM 5. INTEREST IN SECURITIES OF THE ISSUER

(a)      The Reporting Persons beneficially own 3,115,845 shares of
Common Stock representing 8.23% of all of the outstanding shares of
37,853,358 shares of Common Stock outstanding as of August 14, 2012, as
reported by the Issuer. Of the 3,069,845 shares held by the Reporting
Persons on behalf of their clients: Interinvest Corporation Inc.
holds 2,664,345 shares or 7.04% of Issuer's outstanding shares;
Interinvest Consulting Corporation of Canada Limited
holds 1,500 shares for a total of 0.00% of the Issuer's outstanding
shares; and Interinvest (Bermuda) Ltd. holds 404,000 shares for
clients for a total of 1.07% of the Issuer's outstanding shares. Hans P.
Black holds 40,000 shares or 0.11% of the Issuer's outstanding shares
for his own account and 6,000 shares or 0.00% for a related account under
his control.

 (b)      The Reporting Persons may be deemed to have the shared power to
vote or to direct the vote of (and the shared power to dispose of or
direct the disposition of) the 3,115,845 shares of Common Stock held.
This power is shared with the Reporting Persons' investment advisory
clients where applicable. Hans P. Black, by virtue of his relationship to
each of Interinvest Corporation Inc., Interinvest Consulting Corporation
of Canada Limited, and Interinvest (Bermuda) Ltd. may be deemed to
indirectly beneficially own 3,115,845 shares of Common Stock. Hans P.
Black disclaims beneficial ownership of such Common Stock for all other
purposes.

(c)      The following describes all the transactions in Common Stock
that were effected during the past sixty days by the Reporting Persons.


Transaction   Numberof		Price/	Type of
Date		Shares	Cost	Share	Transaction

Interinvest Corporation Inc.
9/7/2012	50,000	$42,620	$0.85	Buy
9/12/2012	20,000	$17,610	$0.88	Buy
9/13/2012	29,845	$25,655	$0.86	Buy
9/21/2012	20,000	$16,972	$0.85	Buy
9/25/2012	20,000	$16,788	$0.84	Buy
9/26/2012	20,000	$16,934	$0.85	Buy
9/27/2012	25,000	$21,235	$0.85	Buy
10/2/2012	30,000	$26,193	$0.87	Buy





Interinvest (Bermuda) Ltd.
None


Interinvest Consulting Corporation of Canada Limited
None



Dr. Hans P. Black
None







(d)	The investment advisory clients of Interinvest Corporation Inc.,
Interinvest Consulting Corporation of Canada Limited, and Interinvest
(Bermuda) Ltd. have the sole right to receive and the sole power to
direct the receipt of dividends from, and the proceeds of sale of,
any of the Securities beneficially owned by such Reporting Persons on
behalf of such clients.  No such client has an interest that relates
to more than 5% of the Common Stock.


(e)	Not applicable


ITEM 6. CONTRACTS, ARRANGEMENTS, UNDERSTANDINGS OR RELATIONSHIPS WITH
RESPECT TO SECURITIES OF THE ISSUER

None of the shares of Common Stock held by the Reporting Persons have
been pledged or are otherwise subject to a contingency the occurrence of
which would give a  third party voting power or investment power over the
Common Stock.

ITEM 7. MATERIAL TO BE FILED AS EXHIBITS

Exhibit 99.1	Joint Filing Agreement, dated as of December 12, 2008
among Interinvest Corporation Inc., Interinvest Consulting Corporation of
Canada Limited, Interinvest (Bermuda) Ltd., and Hans P. Black

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true,
complete and correct.

Date: October 4, 2012

	Interinvest Corporation Inc.

	By: /s/ Stanley T. Schmidt
	Stanley T. Schmidt
	President,Interinvest Corporation Inc.


	Interinvest Corporation of Canada Limited
	By: /s/ Hans P. Black
	Hans P. Black
	Chairman


	Interinvest (Bermuda) Limited
	By: /s/ Hans P. Black
	Hans P. Black
	Director




	By: /s/ Hans P. Black
	Hans P. Black









	EXHIBIT 99.1

JOINT FILING AGREEMENT

In accordance with the Rule 13d-1(k)(1) under the Securities Exchange Act
of 1934, as amended, each of the undersigned hereby agrees to the joint
filing, along with all other such undersigned, on behalf of the Reporting
Persons (as defined in the joint filing), of a statement on Schedule D
(including amendments thereto) with respect to the common stock of the
Issuer (as defined in the attached Schedule 13D), and agrees that this
agreement be included as an exhibit to such joint filing. This agreement
may be executed in any number of counterparts, all of which taken
together shall constitute one and the same instrument.

IN WITNESS WHEREOF, each of the undersigned has executed this agreement
as of this 12th day of December, 2008.


Interinvest Corporation, Inc.

By: /s/ Stanley T. Schmidt
Stanley T. Schmidt
President


Interinvest Corporation of Canada Limited

By: /s/ Hans P. Black
Hans P. Black
Chairman



Interinvest (Bermuda) Limited

By: /s/ Hans P. Black
Hans P. Black
Director




By: /s/ Hans P. Black
Hans P. Black








CUSIP No. 034918102		Page 9 of 10