CONFIDENTIAL INFORMATION HAS BEEN OMITTED PURSUANT TO RULE 406 UNDER THE
SECURITIES ACT AND HAS BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION. THE LOCATIONS OF THE OMITTED INFORMATION HAVE BEEN INDICATED WITH
ASTERISKS.


                                                                    EXHIBIT 10.4

                        PLUG POWER TRADEMARK AGREEMENT


     This Agreement is dated and effective as of February 2, 1999, between PLUG
POWER, L.L.C. ("LICENSOR"), a Delaware limited liability company, and GE FUEL
CELL SYSTEMS, LLC ("LICENSEE"), a Delaware limited liability company.

     A.  Whereas, LICENSOR owns the LICENSED MARKS (hereinafter defined) and
LICENSOR has common law and/or statutory rights therein, including applications
to register and registrations therefor in certain countries throughout the world
for various goods and services;

     C.  Whereas, LICENSEE desires to use the LICENSED MARKS on or in connection
with PRODUCTS, PRE-COMMERCIAL UNITS and SERVICES (each hereinafter defined);

     D.  Whereas, LICENSOR is willing to grant licenses to LICENSEE to use the
LICENSED MARKS on PRODUCTS and PRE-COMMERCIAL UNITS marketed and sold by or on
behalf of LICENSEE, and for SERVICES performed by or on behalf of LICENSEE, in
strict accordance with STANDARDS OF QUALITY (hereinafter defined);

     E.  Whereas, LICENSEE has adopted the corporate name "GE Fuel Cell Systems,
LLC".

     F.  Whereas, LICENSOR is willing to permit the use of the LICENSED MARKS
under the terms and conditions hereinafter set forth.

     NOW THEREFORE, the parties agree as follows:


                                   ARTICLE I
                                  DEFINITIONS

The following terms as used in this Agreement shall have the meaning set forth
in this Article I:

     A.  The term "LICENSED MARKS" shall mean and be limited to the trademarks,
service marks, and logos shown in Exhibit A attached hereto, as such exhibit may
be modified by LICENSOR, from time to time, in its sole discretion.

     B.  The terms "PRODUCTS", "PRE-COMMERCIAL UNITS", and "SERVICES" shall have
the respective meanings set forth in the Distributor Agreement between LICENSEE
and LICENSOR, of even date herewith (the "Distributor Agreement").

     C.  The term "STANDARDS OF QUALITY" shall mean and be limited to the
specifications for PRODUCTS, PRE-COMMERCIAL UNITS, and SERVICES set forth in the
Distributor Agreement.

     D.  The term "LICENSED TERRITORY" shall mean and be limited to every
country, province, territory, or other principality in the world, except the
states of Michigan, Indiana, Ohio and Illinois in the


United States of America while Edison Development Corporation has exclusive
rights to market and sell products similar to Products and provide services
similar to Services therein. In the event that Edison Development Corporation
("EDC") shall lose any of its rights to market and sell similar products and
provide similar services in the States of Michigan, Indiana, Ohio and Illinois
(the "EDC Territory"), this definition of "LICENSED TERRITORY" shall be expanded
to include the EDC Territory.


                                  ARTICLE II
                                 LICENSE GRANT

     A.  LICENSOR hereby grants to LICENSEE, during the term of this Agreement,
a royalty-bearing, non-exclusive license to use the LICENSED MARKS in the
LICENSED TERRITORY on or in connection with the PRODUCTS, PRE-COMMERCIAL UNITS,
and SERVICES, in strict accordance with the STANDARDS OF QUALITY.  LICENSEE is
authorized to use the LICENSED MARKS only on or in connection with PRODUCTS,
PRE-COMMERCIAL UNITS, and SERVICES, including use in packaging, labeling,
general publicity, letterheads, signs and other forms of advertising,
instruction books, and other literature relating to PRODUCTS, PRE-COMMERCIAL
UNITS, and SERVICES.  In no event, however, shall LICENSEE use the LICENSED
MARKS as part of a trade name or authorize others to do so, except as may be
expressly provided for in this Agreement.

     B.  LICENSEE shall have the right to sub-license the use of the LICENSED
MARKS to third parties with which LICENSEE enters into authorized written sub-
contracts for the marketing, sale, and resale of PRODUCTS and PRE-COMMERCIAL
UNITS and the provision of SERVICES, subject to the terms and conditions of this
Agreement and the Distributor Agreement.


                                  ARTICLE III
          EXAMINATION OF PRODUCTS, PRE-COMMERCIAL UNITS, AND SERVICES

     A.  LICENSEE shall use the LICENSED MARKS only on and in connection with
PRODUCTS, PRE-COMMERCIAL UNITS, and SERVICES, and then only to the extent that
such use is in strict accordance with the STANDARDS OF QUALITY.

     B.  LICENSOR or its authorized representative shall have the right at any
time or times to conduct during regular business hours an examination of
LICENSEE's manner of marketing and selling PRODUCTS and PRE-COMMERCIAL UNITS and
performing SERVICES under the LICENSED MARKS and of the facilities where
PRODUCTS and PRE-COMMERCIAL UNITS are marketed and sold and SERVICES are
performed.  LICENSEE shall furnish to LICENSOR, from time to time as requested,
representative samples of PRODUCTS and PRE-COMMERCIAL UNITS to which it affixes
the LICENSED MARKS and representative samples showing all other uses of the
LICENSED MARKS by LICENSEE.  If, at any time, PRODUCTS, PRE-COMMERCIAL UNITS, or
SERVICES sold or performed under the LICENSED MARKS by LICENSEE fail, in the
sole opinion of LICENSOR, to conform to any of the required STANDARDS OF QUALITY
or any other requirement in this agreement, and LICENSOR notifies LICENSEE of
such failure, LICENSEE shall promptly cease marketing and performing such non-
conforming PRODUCTS, PRE-COMMERCIAL UNITS and SERVICES.

                                      -2-


                                  ARTICLE IV
                           USE OF THE LICENSED MARKS

     A.  LICENSEE shall comply with LICENSOR's written guidelines and rules
provided to LICENSEE from time to time by LICENSOR with respect to the
appearance and manner of use of the LICENSED MARKS.  Any form of use of the
LICENSED MARKS not specifically provided for by such guidelines and rules shall
be adopted by LICENSEE only upon prior approval in writing by LICENSOR.
Representative specimens showing the use of the LICENSED MARK by LICENSEE shall
be sent to LICENSOR from time to time upon request by LICENSOR.

     B.  LICENSEE shall comply with all applicable laws and regulations,
including those pertaining to the proper use and designation of trademarks,
corporate names and trade names in the LICENSED TERRITORY and pertaining to the
sale of PRODUCTS and PRE-COMMERCIAL UNITS and the rendering of SERVICES in the
LICENSED TERRITORY.

     C.  LICENSEE shall immediately cease use of the LICENSED MARKS upon notice
from LICENSOR that, in the sole opinion of LICENSOR, such use of the LICENSED
MARKS (i) is in violation of LICENSOR's guidelines, rules, or STANDARDS OF
QUALITY, or (ii) results or is likely to result in an adverse claim against
either LICENSOR or LICENSEE by a third party.

     D.  If, in the sole discretion of LICENSOR, it is required or advisable for
the purpose of making this Agreement enforceable, or for the purpose of
maintaining, enhancing, or protecting LICENSOR's rights in the LICENSED MARKS,
to record this Agreement or to enter LICENSEE as registered or authorized user
of the LICENSED MARKS, LICENSOR will attend (at LICENSEE's expense) to such
recording or entry.  LICENSEE will execute and deliver to LICENSOR such
additional instruments or documentation as LICENSOR may reasonably request,
including without limitation execution and delivery of substitute or short-form
license agreements, with terms consistent with this Agreement, for recordation
or registration in specified countries in the event that this Agreement shall be
deemed to be unsuitable for recordation or entry in such countries.  The terms
and conditions of this Agreement (and not the terms and conditions of such
substitute or short-form license agreements entered into for recording or entry
purposes) shall be binding between the parties throughout the world and shall
govern and control any controversy that should arise with respect to each
party's rights and obligations hereunder; provided, however, that if specific
                                          --------  -------
terms and conditions of any such substitute or short-form agreement differ from
the comparable terms and conditions of this Agreement and enforcement of the
comparable terms and conditions of this Agreement pursuant to this provision
either would be improper under the laws of the applicable country or would
adversely affect LICENSOR's rights in the LICENSED MARKS in such country, then
the specific terms and conditions of the substitute or short-form agreement
shall be controlling in such country.

     E.  LICENSEE shall supply LICENSOR with such information concerning the use
of the LICENSED MARKS by LICENSEE on or in connection with the PRODUCTS, PRE-
COMMERCIAL UNITS, and SERVICES as LICENSOR may reasonably request to aid
LICENSOR in the acquisition, maintenance, and renewal of registrations of the
LICENSED MARKS, to record this Agreement and to enter LICENSEE as a registered
or authorized user of the LICENSED MARKS, or for any other purpose.

                                      -3-


                                   ARTICLE V
                   OWNERSHIP AND VALIDITY OF LICENSED MARKS

     A.  LICENSEE admits the validity, and LICENSOR's ownership, of the LICENSED
MARKS and agrees that any and all rights that might be acquired by the use of
the LICENSED MARKS by LICENSEE shall inure to the sole benefit of LICENSOR.
LICENSEE admits and agrees that, as between the parties, LICENSEE has been
extended only a mere permissive right to use the LICENSED MARKS as provided in
this Agreement which is not coupled with any ownership interest.

     B.  Other than as expressly set forth in this Agreement, LICENSEE further
agrees not to use or file any application to register, in any class and in any
country, any trademarks, service marks, trade names, or corporate names
resembling, similar to, or containing, in whole or in part, the LICENSED MARKS.
Whenever the attention of LICENSEE is called by LICENSOR to any such confusion
or risk of confusion, LICENSEE agree to take appropriate steps immediately to
remedy or avoid such confusion or risk of confusion.

     C.  LICENSEE shall give LICENSOR notice of any known or presumed
infringements of the LICENSED MARKS by others, and LICENSEE shall render
LICENSOR full cooperation for the protection of the LICENSE MARKS.  LICENSOR
shall have and retain all rights to bring all actions and proceedings in
connection with infringement or unauthorized use of the LICENSED MARKS at its
sole discretion, and LICENSEE shall have no rights to make any such claims or
bring any actions or proceedings, whether in its own name or on behalf of
LICENSOR, without the express prior written consent of LICENSOR.  If LICENSOR
decides to enforce its rights in the LICENSED MARKS against an infringer, all
costs incurred and recoveries made shall be for the account of LICENSOR.


                                  ARTICLE VI
                             ROYALTIES AND REPORTS

A.   LICENSEE shall pay LICENSOR royalties at the rate of [***] of the net
selling price of PRODUCTS, PRE-COMMERCIAL UNITS, and SERVICES sold or otherwise
disposed of or performed by LICENSEE under one or more of the LICENSEE MARKS.

B.   The term "net selling price" for the purpose of computing royalties means
LICENSEE's gross invoice price for such PRODUCTS, PRE-COMMERCIAL UNITS, or
SERVICES, less deduction, to the extent included in the gross invoice price, of
regular trade and quantity discounts, insurance, shipping, sales taxes and
return credits. PRODUCTS, PRE-COMMERCIAL UNITS, and SERVICES shall be considered
to be sold when billed, except that upon any termination or expiration of this
Agreement, all SERVICES performed, and all shipments of PRODUCTS and
PRE-COMMERICAL UNITS made, on or prior to the date of such expiration or
termination which have not been billed prior thereto shall be considered to have
been sold (and therefore subject to royalty). Where PRODUCTS, PRE-COMMERCIAL
UNITS, or SERVICES are not sold, but are otherwise disposed of or performed, the
net selling price of such PRODUCTS, PRE-COMMERICAL UNITS, or SERVICES shall be
the net selling price of products or services of like kind and quality being
offered for sale by LICENSEE or, in the event that LICENSEE is not offering such
similar products or services, the net selling price that would reasonably be
anticipated by LICENSOR in the event that such PRODUCTS, PRE-COMMERCIAL UNITS,
or SERVICES were being offered by LICENSEE. The term "otherwise disposed of or
performed" as used herein shall refer to (i) PRODUCTS or PRE-COMMERCIAL UNITS
put into use by LICENSEE for any purpose other than routine testing, (ii)
PRODUCTS, PRE-COMMERCIAL UNITS, and SERVICES not sold but otherwise delivered
to, or performed for, others regardless of the basis of compensation, if any,
and (iii) PRODUCTS, PRE-COMMERCIAL UNITS, and SERVICES sold to others for
compensation which is less than the compensation which be paid by a willing
unaffiliated buyer to a willing unaffiliated seller in an arm's length
transaction. In order to assure to LICENSOR the full royalty payments
contemplated in this Agreement, LICENSEE agrees that, in the event that any
PRODUCTS, PRE-COMMERCIAL UNITS, or SERVICES for which royalties are payable
shall be sold for resale to a party that is affiliated with LICENSEE (or to and
through a series of such affiliated parties), the royalties to be paid with
respect to such PRODUCTS, PRE-COMMERCIAL UNITS, or SERVICES shall be computed
upon the net selling price at which such PRODUCTS, PRE-COMMERCIAL UNITS, or
SERVICES are finally to a non-affiliated party.

CONFIDENTIAL INFORMATION HAS BEEN OMITTED PURSUANT TO RULE 406 UNDER THE
SECURITIES ACT AND HAS BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION. THE LOCATIONS OF THE OMITTED INFORMATION HAVE BEEN INDICATED WITH
ASTERISKS.


                                      -4-






     C.  LICENSEE agrees to make written reports to LICENSOR quarterly within
thirty (30) days after the first days of each January, April, July, and October
during the term of this Agreement, and effective as of such dates, stating in
each such report the description and aggregate net selling prices of PRODUCTS,
PRE-COMMERCIAL UNITS, and SERVICES sold or otherwise disposed of or performed
during the preceding three (3) calendar months and upon which royalties are
payable hereunder.  The first such report shall include all such PRODUCTS, PRE-
COMMERCIAL UNITS, and SERVICES sold or otherwise disposed of or performed
between the effective date of this Agreement and the date of such first report.
LICENSEE also agrees to make a written report to LICENSOR within thirty (30)
days after any expiration or termination of this Agreement, stating in such
report the description and aggregate net selling prices of PRODUCTS, PRE-
COMMERCIAL UNITS, and SERVICES sold or otherwise disposed of or performed and
upon which royalties are payable hereunder, but which have not been previously
reported to LICENSOR.

     D.  Concurrently with the making of each report pursuant to Paragraph VI.C.
hereof, LICENSEE shall pay to LICENSOR royalties at the rate specified by
Paragraph VI.A. hereof on all PRODUCTS, PRE-COMMERCIAL UNITS, and SERVICES
included therein.  All payments to be made under this Agreement shall be made in
the City of New York, State of New York, U.S.A. in United States Dollars by
electronic transfer to an account designated by LICENSOR.  Where the provisions
of this Agreement require the conversion into United States Dollars of an amount
initially computed in the currency of another country, the amount of United
States Dollars payable under this Agreement shall be determined on the basis of
the applicable exchange rate quoted by The Wall Street Journal, Eastern Edition,
most recently prior to the date each such payment is made or due, whichever is
earlier.  If no exchange rate is quoted for any period, LICENSOR shall determine
the rate in accordance with an alternative LICENSOR deems reasonable.

     E.  LICENSEE shall keep records, in sufficient detail to enable the
royalties payable hereunder by LICENSEE to be determined, for at least a period
of two years following the expiration or termination of this Agreement.
LICENSEE shall permit its books and records to be examined from time to time
upon reasonable written notice to the extent necessary to verify the reports
provided for hereunder, such examination to be made at the expense of LICENSOR
by any auditor appointed by LICENSOR who shall




                                      -5-



be acceptable to LICENSEE, or, at the option and expense of LICENSEE, by a
certified independent accountant appointed by LICENSOR and approved by LICENSEE,
which approval shall not be unreasonably withheld.


                                  ARTICLE VII
                                  TERMINATION

     A.  Until terminated pursuant to any provision of this Article VII, this
Agreement shall have a term of five (5) years from its effective date.
Notwithstanding the foregoing, this Agreement shall automatically terminate
without further notice in the event that the Distributor Agreement terminates
without being replaced by another such agreement between the parties thereto.

     B.  This Agreement shall terminate as to a particular country with notice
on a date established by either LICENSOR or LICENSEE if a controlling substitute
or short-form agreement is required in such country pursuant to Paragraph IV.D.
hereof and such controlling replacement agreement contains provisions
unacceptable to the party giving notice hereunder.

     C.  In the event LICENSEE does not comply with any provisions of this
Agreement and LICENSOR elects to give LICENSEE written notice of such non-
compliance, LICENSEE shall have twenty (20) days from the receipt of such notice
to remedy such non-compliance.  If such non-compliance is not remedied within
said twenty (20) days, LICENSOR shall have the right to terminate this Agreement
at any time thereafter by giving LICENSEE written notice of the effective date
of such termination.

     D.  Upon any termination of this Agreement for any reason, LICENSEE agrees
to cease and discontinue completely further use of the LICENSED MARKS; provided,
however, that LICENSEE shall have a period of three (3) months from the date of
such termination to fill any outstanding orders for PRODUCTS, PRE-COMMERCIAL
UNITS, or SERVICES placed prior to the effective date of termination (provided,
however, such terminal use shall comply with the other provisions of this
Agreement).  At the expiration of such three (3) month period, LICENSEE shall
have no further right to use the LICENSED MARKS, or any mark the same as,
substantially similar to, or likely to cause confusion with the LICENSED MARKS.

     E.  The following provisions of this Agreement shall survive any
termination:  Paragraph IV.D., Paragraph IV.E., Paragraph V.A., Paragraph V.B.,
Paragraph V.C. Article VI, Paragraph VII.D., Paragraph VII.E, and Paragraphs
VIII.A., C., D., E., and F.


                                 ARTICLE VIII
                           MISCELLANEOUS PROVISIONS

     A.  LICENSEE shall fully indemnify and hold harmless LICENSOR against any
and all claims, losses, damages, expenses or liability asserted against or
suffered by LICENSOR and arising out of or relating to this Agreement or the
sale or disposition of PRODUCTS or PRE-COMMERCIAL UNITS, or performance of
SERVICES, by LICENSEE under the LICENSED MARKS, whether or not such

                                      -6-


PRODUCTS, PRE-COMMERCIAL UNITS, and SERVICES conform to the required STANDARDS
OF QUALITY.

     B.  This Agreement or any rights hereunder may not be assigned or otherwise
transferred or extended by LICENSEE to any party including without limitation
subsidiaries and affiliates of LICENSEE without the written consent of LICENSOR,
and any attempted assignment, transfer or extension without such consent shall
be null and void.

     C.  Any notices or requests with reference to this Agreement shall be in
writing and shall be directed by one party to the other at its respective
address as follows:

     LICENSOR

          Plug Power, L.L.C.
          Attention: President and CEO
          968 Albany-Shaker Road
          Albany, New York 12110

     LICENSEE

          GE FUEL CELL SYSTEMS, L.L.C.
          Attention: President
          One River Road
          Schenectady, NY 12345

Any party may change its address to which notices or requests shall be directed
by notice to the other party, but until such change of address has been
received, any notices or requests sent to the above addresses shall be effective
upon transmittal and shall be considered as having been received.

     D.  This instrument contains the entire agreement between the parties
hereto regarding the use of the LICENSED MARKS, and this Agreement supersedes
and cancels all previous, understandings or agreements in regard to the subject
matter hereof. This Agreement may not be released or modified in any manner,
orally or otherwise, except by an instrument in writing signed by duly
authorized representatives of the parties hereto.

     E.  This Agreement shall be governed by the laws of the State of New York,
United States of America, without regard to its rules regarding the conflict of
laws.

     F.  Failure by LICENSOR at any time to enforce or require strict
compliance with any provision of this Agreement shall not affect or impair that
provision in any way or the rights of LICENSOR to avail itself of the remedies
it may have in respect of any subsequent breach of that or any other provision.

                                      -7-


     IN WITNESS WHEREOF, LICENSOR and LICENSEE have caused this instrument to be
executed in duplicate by their duly authorized representatives as of the date
first written above.


                                   PLUG POWER, L.L.C.
ATTEST:


     /s/ Lou Thomson               By: /s/ Gary Mittleman
- ---------------------------------      -------------------------------------
                                       Gary Mittleman, President and CEO



                                   GE FUEL CELL SYSTEMS, LLC
ATTEST:


     /s/ Lou Thomson               By: /s/ Barry Glickman
- ---------------------------------      -------------------------------------
                                       Barry Glickman, President

                                      -8-


                                   EXHIBIT A



     LICENSED MARK                             REGISTRATION NO.
     -------------                             ----------------


     [PLUG POWER
     LOGO APPEARS HERE]

                                               _______________

                                      -9-