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                                                                   EXHIBIT 10.5

                           TRADEMARK LICENSE AGREEMENT

         THIS TRADEMARK LICENSE AGREEMENT (this "Agreement"), dated and
effective as of the ________ day of __________________, 2000 ("Effective Date"),
by and between DUKE ENERGY CORPORATION, a North Carolina corporation ("Duke
Energy"), and DUKE ENERGY FIELD SERVICES, LLC, a Delaware limited liability
company ("Licensee").

         WHEREAS, substantially contemporaneously herewith, DEFS Holding Corp.,
a Delaware corporation and a wholly-owned subsidiary of Duke ("DEFS Holding"),
and Phillips Gas Company, a Delaware corporation and a wholly-owned subsidiary
of Phillips Petroleum Company, a Delaware corporation ("PGC"), have entered into
an Amended and Restated Limited Liability Company Agreement of Duke Energy Field
Services, LLC pursuant to which DEFS Holding and PGC have transferred to
Licensee certain of their midstream natural gas gathering, processing and
marketing operations and assets (the "Pooled Assets"); and

         WHEREAS, Licensee desires to obtain a license from Duke Energy to
utilize the Licensed Marks (hereinafter defined) for a limited period of time
solely for the purpose of operating the Pooled Assets; and

         WHEREAS, Duke Energy is willing to grant such license on the terms and
conditions more fully set forth below;

         NOW, THEREFORE, for and in consideration of the premises and the mutual
covenants contained herein, and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
agree as follows:

         1. The term "Licensed Marks" shall mean the name and mark "Duke Energy"
and the stylized "D" logotype in connection with that name and mark
(collectively, the "Licensed Marks").

         2. The term "Licensed Goods and Services" shall mean those goods and
services which were being sold, distributed or provided as part of the
businesses comprising the Pooled Assets as of the Effective Date.

         3. The term "Licensed Territory" shall mean the continental United
States and Canada.

         4. Duke Energy hereby grants to Licensee a nonexclusive, royalty-free
license to use, in the Licensed Territory in connection with the advertising,
sale, rendering and distribution of the Licensed Goods and Services for the term
of this Agreement, when used in the specific manner authorized herein, (a) the
name and mark "Duke Energy" as part of the names "Duke Energy Field Services"
and "Duke Energy Field Services, LLC" and (b) the stylized "D" logotype in
connection with those two names. Licensee shall not have the right to register,
as trademarks, service marks or trade names, the Licensed Marks in the Licensed
Territory or elsewhere or to sublicense the Licensed

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Marks. Except as expressly granted in this Agreement, Licensee shall have no
license of, right to use or interest in the Licensed Marks or any other
trademark, service mark, trade name or logo owned, licensed or used by Duke
Energy, including any related applications or registrations (collectively, the
"Duke Energy Marks").

         5. Licensee may use the Licensed Marks only in connection with its
advertising, sale, rendering and distribution of the Licensed Goods and Services
in the Licensed Territory, inclusive of such modifications and improvements to
the Licensed Goods and Services as do not comprise materially different goods
and services. The specific manner of use of the Licensed Marks always shall be
subject to the prior written approval of Duke Energy. Licensor shall retain the
right, from time to time, and in its sole discretion, to modify, amend, alter or
discontinue any of the Licensed Marks. When Licensor gives Licensee written
notice, Licensee shall promptly, but in no event later than 180 days after the
notice, conform or discontinue, as applicable, its use of the Licensed Marks as
so modified, altered, amended or discontinued and the definition of Licensed
Marks shall be deemed to be automatically amended into conformity with those
changes in the Licensed Marks. Licensee shall disclose to the public, on its
packaging, advertising and literature for the Licensed Goods and Services that
the Licensed Marks are owned by Duke Energy and are licensed for use by
Licensee. Licensee shall not otherwise make any reference to Duke Energy in
Licensee's advertising, promotion, sale or rendering of the Licensed Goods or
Services without the prior written approval of Duke Energy. Licensee also shall
use on its packaging, labels and in its advertising and literature for the
Licensed Goods and Services its own name and address, identifying Licensee as
the manufacturer, distributor and/or provider of the Licensed Goods or Services.
Licensee may not use in connection with the Licensed Goods or Services, or on
packaging, advertising materials or literature for the Licensed Goods or
Services, any other name or mark (except for Licensee's name and the Licensed
Marks) without Duke Energy's prior written approval.

         6. Licensee acknowledges that title and ownership in the Licensed Marks
and the Duke Energy Marks and the associated goodwill are and shall at all times
remain in Licensor and that, by this Agreement or otherwise, Licensee shall not
acquire any title, ownership, or other interest in the Licensed Marks or the
Duke Energy Marks. All uses of the Licensed Marks by Licensee and all goodwill
generated by those uses shall inure exclusively and completely to the benefit of
Licensor. Licensee acknowledges the validity and enforceability of the
Licensor's rights and title in the Licensed marks and the Duke Energy Marks and
shall not contest or challenge the validity of, or Licensor's title in, the
Licensed Marks or the Duke Energy Marks.

         7. Licensee represents, warrants and covenants that the Licensed Goods
and Services shall not be manufactured, packaged, distributed, sold or rendered
in such a way as to constitute or be likely to constitute a health or safety
hazard to consumers or others. Licensee covenants and agrees that the Licensed
Goods and Services and Licensee's use of the Licensed Marks shall comply fully
with all applicable state, federal, national and local laws and regulations,
including those governing the manufacturing, packaging, distribution, sale or
rendering of the Licensed Goods and


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Services, and that the Licensed Goods and Services shall be at least of good and
merchantable quality.

         8. Licensee agrees, at its expense, to submit to Duke Energy, promptly
upon Duke Energy's request, samples of the Licensed Goods, as well as specimens,
labels, advertising, promotional materials and other literature showing actual
use of the Licensed Marks in connection with the Licensed Goods and Services. If
at any time Duke Energy advises Licensee of changes which must be made in the
manner of Licensee's use of the Licensed Marks, Licensee agrees promptly to make
such changes requested by Duke Energy or, in the alternative, voluntarily to
terminate this Agreement.

         9. Licensee agrees that Duke Energy, or persons authorized by Duke
Energy, may enter and inspect, during all reasonable hours, Licensee's business
premises where the Licensed Goods and Services are manufactured, assembled,
stopped, distributed or rendered, such inspection being for the sole purpose of
Duke Energy maintaining control of the nature and quality of the Licensed Goods
and Services in connection with which the Licensed Marks are being used.

         10. Any cause of action for infringement or unfair competition arising
from or in connection with the use by others of marks consisting of or
confusingly similar to the Licensed Marks may be prosecuted at the sole option
of Duke Energy and at Duke Energy's expense; however, Duke Energy shall not be
obligated to bring or to prosecute any cause of action. In the event of such
action, Licensee agrees to render all reasonable assistance to Duke Energy for
the institution and prosecution of such action.

         11. Licensee agrees to indemnify, defend and hold Duke Energy and
its directors, officers, employees, and subsidiaries (collectively, "Indemnified
Persons") harmless from any and all claims, liabilities, demands, actions,
causes of action, suits, loss or damage (including their reasonable attorneys'
fees and costs of court) arising out of any property damage, injury or death
of any person resulting, or alleged to have resulted, from the design,
manufacture, use, sale or marketing of the Licensed Goods and Services,
REGARDLESS OF WHETHER ANY INDEMNIFIED PERSON AND/OR OTHERS MAY BE WHOLLY,
PARTIALLY OR SOLELY NEGLIGENT OR OTHERWISE AT FAULT AND REGARDLESS OF WHETHER
SUCH CLAIM OR LIABILITY MAY BE BASED UPON NEGLIGENCE OR STRICT LIABILITY.

         12. Licensee agrees to indemnify, defend and hold all Indemnified
Persons Duke Energy harmless from any and all claims, liabilities, demands,
actions, causes of action, suits, loss or damage (including their reasonable
attorneys' fees and costs of court) based in whole or in part on any claim (a)
that the Licensed Goods and Services or the advertising, promotional, packaging
or other materials of Licensee infringe the U.S. or foreign patent, trademark,
service mark, trade name or copyright rights of any person, party, or entity,
(b) that the Licensed Goods and Services incorporate or misappropriate the
confidential business information or trade secrets of any person, party or
entity, or (c) that the packaging, advertising, promotional or other printed
materials produced or distributed


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in connection with the Licensed Goods and Services infringe the copyright of any
person, party or entity, REGARDLESS OF WHETHER ANY INDEMNIFIED PERSON AND/OR
OTHERS MAY BE WHOLLY, PARTIALLY, OR SOLELY NEGLIGENT OR OTHERWISE AT FAULT AND
REGARDLESS OF WHETHER SUCH CLAIM OR LIABILITY MAY BE BASED UPON NEGLIGENCE OR
STRICT LIABILITY.

         13. Licensee agrees that it shall maintain in force a commercial
general liability insurance policy including vendor's coverage and product
liability coverage for the Licensed Goods and Services in the form and with an
insurance carrier acceptable to Duke Energy, with minimum limits of liability of
$1,000,000 per occurrence. Such policy shall include an endorsement expressly
naming Duke Energy as an additional insured with subrogation waived in its favor
and stating that Duke Energy shall receive thirty (30) days prior notice of
cancellation, material change in coverage or intent not to renew. Licensee
shall, within thirty (30) days after the singing of this Agreement, deliver to
Duke Energy a copy of such insurance policy and endorsements certified within
the last thirty (30) days by the insurance carrier. Licensee shall deliver to
Duke Energy certified copies of all changes to the policy within 60 days after
the applicable change and additional certificates of insurance annually on the
anniversary date of this Agreement.

         14. This Agreement may be assigned by Licensee to any successor in
interest to all, or substantially all, of Licensee's business and assets related
to the Licensed Goods and Services including, without limitation, to any
publicly owned corporation which may acquire all or substantially all of
Licensee's assets related to the Licensed Goods and Services, in which event
such successor or assignee shall assume all of the rights and obligations of
"Licensee" hereunder. This Agreement, and the license herein granted may not
otherwise be assigned by Licensee without Duke Energy's prior written approval.
Duke Energy shall have the right to assign, transfer, sub-contract or otherwise
delegate the performance of some or all of its rights or responsibilities under
this Agreement.

         15. This Agreement shall have a term from the Effective Date until
terminated as provided herein below:

                  (a) Licensee may terminate the Agreement at any time, with or
without cause, upon thirty (30) day's advance written notice to Duke Energy;

                  (b) Duke Energy may terminate the Agreement, on thirty (30)
day's advance written notice, if Duke Energy and Licensee are unable to resolve
any dispute or difference with regard to the manner of use by Licensee of the
Licensed Marks or the nature or quality of the goods or services in connection
with which the Licensed Marks are being used;

                  (c) In the event Licensee shall breach any of its obligations
under this Agreement, Duke Energy may give written notice of such breach. If
Licensee shall not have cured such breach


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within thirty (30) days following such written notice, Duke Energy may send an
additional written notice terminating the Agreement on not less than thirty (30)
day's additional notice;

                  (d) In the event Duke Energy's ownership interest, both direct
and indirect, in Licensee shall, at any time, be less than or equal to thirty
five percent (35%) or in the event Duke Energy no longer controls, directly or
indirectly, the management and policies of the Licensee, Duke Energy may
terminate this Agreement on not less than thirty (30) day's advance written
notice to Licensee; or

                  (e) Licensee is convicted of or pleads guilty or no contest to
a felony or other crime which Duke Energy believes may adversely affect the
reputation or goodwill of the Licensed Marks or Duke Energy.

         16. The obligations of paragraphs 10, 11 and 16 of this Agreement shall
survive termination hereof, regardless of the reason for such termination.

         17. Following termination of this Agreement, regardless of the reason
for termination, Licensee agrees (a) to promptly discontinue all use of the
Licensed Marks and (b) to promptly amend its trade names, limited liability
company agreement, certificates of incorporation or other organizational
documents to remove the Duke Energy name therefrom. Thereafter, Licensee shall
not utilize in any way, any name, mark, phrase or logo incorporating "Duke" or
"Duke Energy" or any of the Licensed Marks, or any name or mark confusingly
similar thereto, including using any of the foregoing as a business name or as a
trademark or service mark in connection with the sale of any goods or services;
PROVIDED, however, that Licensee may continue to use any signage, printed
literature, sales materials, purchase orders and the like and sell any products
that are included in its inventory as of the date of termination which materials
or products utilize the Licensed Marks until the supplies thereof existing on
the date of termination have been exhausted, but in any event not longer than
one hundred eighty (180) days following such termination.

         18. All notices and other communications to be given to any party
hereunder shall be sufficiently given for all purposes hereunder if in writing
and delivered by hand, courier or overnight delivery service or three days after
being mailed by certified or registered mail, return receipt requested, with
appropriate postage prepaid, or when received in the form of a telegram or
facsimile and shall be directed to the address or facsimile number set forth
below (or at such other address or facsimile number as such party shall
designate by like notice):


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                  To Duke Energy:           Duke Energy Corporation
                                            5400 Westheimer Court, 8th Floor
                                            Houston, Texas 77056-5310
                                            Attention: Richard K. McGee
                                            Fax No.: (713) 627-5510

                  To Licensee:              Duke Energy Field Services, LLC
                                            370 17th Street, Suite 900
                                            Denver, Colorado 80202
                                            Attention: Martha B. Wyrsch
                                            Fax No.. (303) 605-8902

         19. This Agreement is entered into and shall be governed for all
purposes by the laws of the State of Texas.

         20. This Agreement may be executed in one or more counterparts, all of
which shall be considered one and the same agreement, and shall become effective
when one or more counterparts have been signed by each of the parties hereto and
delivered (including by facsimile) to the other party.

         21. This Agreement may not be modified or amended except by an
instrument or instruments in writing signed by all parties hereto. Either party
hereto may, only by an instrument in writing, waive compliance by the other
parties hereto with any term or provision of this Agreement on the part of such
other party hereto to be performed or complied with. The waiver by any party
hereto of a breach of any term or provision of this Agreement shall not be
construed as a waiver of any subsequent breach. Except as otherwise expressly
provided herein, no failure to exercise, delay in exercising or single or
partial exercise of any right, power or remedy by any party, and no course of
dealing between the parties, shall constitute a waiver of any such right, power
or remedy.

         22. The parties hereto agree that irreparable damage would occur in the
event that any party fails to consummate the transactions contemplated by this
Agreement in accordance with the terms of this Agreement and that tho parties
shall be entitled to specific performance in such event, in addition to any
other remedy or law or in equity.

         23. Nothing in this Agreement shall be deemed to create a franchise,
joint venture, or partnership between Licensor and Licensee.


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         IN WITNESS WHEREOF, each of the undersigned, intending to be legally
bound, has caused this Agreement to be duly executed and delivered on the date
first set forth above.

                                        DUKE ENERGY CORPORATION


                                        By:
                                           -----------------------------
                                        Name:
                                             ---------------------------
                                        Title:
                                              --------------------------


                                        DUKE ENERGY FIELD SERVICES, LLC


                                        By:
                                           -----------------------------
                                        Name:
                                             ---------------------------
                                        Title:
                                              --------------------------



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