<PAGE>
                                                                   Exhibit 10.17

                                  CONFIDENTIAL

                                 AMENDMENT NO. 3
                                       TO
                            MASTER LICENSE AGREEMENT

                     (formerly the Volume License Agreement)

         THIS AMENDMENT NO. 3 TO MASTER LICENSE AGREEMENT ("Amendment No. 3") is
made and entered into as of this 1st day of July, 2003 by and between Syntroleum
Corporation, a Delaware corporation ("Licensor"), and Ivanhoe Energy Inc., a
company organized under the laws of the Yukon, Canada ("Licensee").

                                    RECITALS

         A. WHEREAS, Licensor and Licensee previously entered into that certain
Volume License Agreement dated as of April 26, 2000, as amended by Amendment No.
1 to Volume License Agreement dated as of October 11, 2000 which, among other
things, changed the Volume License Agreement to a Master License Agreement.
(collectively, the "Master License Agreement") and by Amendment No. 2 dated June
1, 2002; and

         B. WHEREAS, Licensor and Licensee desire to amend certain provisions of
the Master License Agreement as set forth in this Amendment No. 3.

         NOW, THEREFORE, in consideration of the mutual covenants and agreements
set forth in this Amendment No. 3, the Parties agree as follows. Unless
otherwise provided in this Amendment No. 3, capitalized terms used in this
Amendment No. 3 but not defined shall have the meanings set forth in the Master
License Agreement.

         1. The definition of "Licensed Territory" at Section 1.15 of the Master
License Agreement and Section 1.16 of the Site License Agreement is amended to
read as follows:

         "LICENSED TERRITORY" means all the countries of the world and their
         respective territorial waters, including the United States of America,
         Canada, Mexico, the People's Republic of China, India, and their
         respective territorial waters, except for
<PAGE>

         any country and its territorial waters (i) that, from time to time, may
         be prohibited, or whose citizens (considered as a group) may be
         prohibited, by the United States government from receiving Licensor
         Technology or the products thereof or (ii) the inclusion of which in
         the definition of Licensed Territory is, or could in good faith be
         argued to be, prohibited by United States law, including, without
         limitation, United States Executive Orders and administrative orders,
         rules and regulations. Licensed Territory shall include territories or
         territorial waters which are the subject of official dispute between or
         among countries only if all countries claiming sovereignty, a sovereign
         right, or jurisdiction over such territories or territorial waters are
         otherwise included within the definition of such term.

         2. Paragraph 5 of Amendment No. 1 is amended to delete the final
sentence of Paragraph 5. Paragraph No. 5 shall now read as follows:

                  In consideration for the rights granted to Licensee by
         Licensor under this Amendment No. 1., Licensee shall pay Licensor a
         non-refundable amount of $7,000,000 U.S. dollars upon execution of this
         Amendment No. 1. This amount, as well as the previous payment of $3
         million under the original Volume License Agreement, dated April 26,
         2000, shall not be credited against the first $10,000,000 U.S. dollars
         in License Fees payable by Licensee to Licensor as partial
         reimbursement for the research and development costs previously
         incurred by Licensor.

         3. Section 2.01 of the Master License Agreement is hereby amended to
add the following sentence at the end of the section:

                  With respect to any Licensed Plant Licensee wishes to develop
         in India and the People's Republic of China, Licensor and Licensee
         shall develop additional procedures to protect intellectual property;
         Licensor shall have the final approval in respect of any intellectual
         property protection procedures and participants and contractors
         involved in a
<PAGE>

         Licensed Plant in those countries, which approval shall not be
         unreasonably withheld. Such participants shall not exclude China
         International Trust and Investment Corporation and national energy
         companies.

         4. Except as expressly amended by this Amendment No. 3, the Master
License Agreement is and shall remain in full force and effect in accordance
with its terms and the parties hereby ratify and reaffirm the Master License
Agreement as amended hereby.

                                       Licensor
                                       SYNTROLEUM CORPORATION

                                       By: /s/ K. R. Roberts
                                           -------------------------------------
                                           Ken Roberts, Senior Vice President

                                       Licensee
                                       IVANHOE ENERGY INC.

                                       By: /s/ E. L. Daniel
                                           -------------------------------------
                                           E. Leon Daniel, President & CEO


<PAGE>

                         Exhibit A to Amendment Number 2

                                  ATTACHMENT 3

                           to Master License Agreement

                             LICENSE FEE CALCULATION

I.    For purposes of this Attachment 3, the following terms shall have the
      meanings ascribed thereto:

A.    "LICENSED PLANT" means the Licensed Plant in which a Site License
      Agreement for such plant is issued to and remains in the name of the
      Licensee who has executed this Agreement with Licensor and, in which the
      Participating Interest held by Licensee, or collectively by Licensee and
      any other Person who has executed a license agreement (which is applicable
      to the Licensed Plant) with Licensor, represents at least 10% of the
      entire Participating Interest not held by a governmental authority
      regardless of operatorship of the Licensed Plant.

B.    "LARGE LICENSED PLANT" means a Licensed Plant under a single Site License
      Agreement with a maximum daily design capacity, as defined in a single
      Process Design Package, of nominally 180,000 or more barrels of Synthetic
      Product per day and which may be constructed in two phases of nominally
      90,000 or more barrels per day for each phase and with the second phase
      constructed either concurrently with the first phase or in a separate
      consecutive period starting no more than 1 year following the start of
      construction of the first phase.

C.    "ROYALTY RATE" shall mean (i) the lowest royalty rate per Barrel of
      Synthetic Product accepted by Licensor for a Site License Agreement with a
      non-Affiliate for a facility of comparable size, in the Licensed
      Territory, which is not under a master preferred license agreement, during
      the twelve (12) months immediately preceding the execution date of the
      applicable Site License Agreement under this Agreement, or (ii) if no such
      Site License Agreement has been executed during the twelve (12) months
      immediately preceding, then the royalty rate per Barrel of Synthetic
      Product in the last Site License Agreement with a non-Affiliate, in the
      Licensed Territory, executed by Licensor, which is not under a master
      preferred license agreement, or (iii) if none of the foregoing applies,
      then US$0.50 per Barrel of Synthetic Product. Market Royalty Rate does not
      include the catalyst price as provided for under Section 2.03 of this
      Agreement.

D.    "BLS INDEX" shall mean the index for January of the year in question
      represented by the Producer Price Index for Industrial Commodities as
      published by the Bureau of Labor Statistics, U.S Department of Labor,
      using the year 1982 as the base index equal to 100. If, at any time, the
      above index should cease to be published, then
<PAGE>

      another suitable index published by the U.S. Government or other
      authoritative organization and generally recognized by the trade as
      authoritative with respect to changes in the U.S. of equivalent commodity
      costs shall be used.

II.   For each Site License Agreement executed under this Agreement for a
      Licensed Plant with a maximum daily design capacity, as defined by the
      Process Design Package, of less than 30,000 barrels of Synthetic Product
      per day, Licensee agrees to pay License Fees to Licensor on a prepaid
      license basis as follows.

         A.    Licensee agrees to pay Licensor a one-time, prepaid License Fee
               calculated in accordance with the following formula:

               License Fee = "C" x 350 x 7.5 x "R" wherein:

                  "C" =    the maximum daily design capacity, as defined by the
                           Process Design Package, of such Licensed Plant to
                           produce Marketable Products measured in Barrels of
                           Synthetic Product per day for which such Licensed
                           Plant is originally designed and constructed, and

                  "R" =    the Royalty Rate.

               and payable in installments as follows:

                  (i)    20% within thirty (30) days after the execution of the
                         Site License Agreement for such Licensed Plant;

                  (ii)   30% within thirty (30) days after delivery of the
                         Process Design Package or within one hundred twenty
                         (120) days after the execution of the Site License
                         Agreement for such Licensed Plant, whichever first
                         occurs;

                  (iii)  20% within thirty (30) days after the commencement of
                         field construction move-in;

                  (iv)   30% within one-hundred and twenty (120) days after the
                         Start-Up Date of the Licensed Plant or a successful
                         Performance Test as specified in the Process Guarantee
                         and Performance Test Agreement, whichever first occurs.

         B.    Notwithstanding any other provision of this Agreement, payments
               made by Licensee to Licensor under Section 5.01 of this Agreement
               and Section 5 of Amendment No. 1 to Volume License Agreement
               between Licensee and Licensor dated October 11, 2000, shall be
               fully credited against the License Fees payable by Licensee to
               Licensor under Section II.A.
<PAGE>

         C.    In the event the actual production capacity of any Licensed
               Plant, under II.A. above, is determined to have either exceeded
               the original maximum daily design capacity established in its
               Site License Agreement or is increased through major equipment
               modification, by more than five percent (5%) or by more than 500
               barrels per day, at any time after the Start-up Date, Licensee
               shall pay Licensor an additional License Fee, on a prepaid basis,
               equal to the difference between (a) the prepaid License Fee as
               would have been calculated with the higher production capacity
               for such Licensed Plant substituted for "C" in the calculation
               method set forth in II.A. above, and (b) the License Fee as would
               have been calculated for such Licensed Plant by the method set
               forth in II.A. above using the original maximum daily design
               capacity established in each Site License Agreement. The
               incremental License Fee due will be reduced by any previous
               incremental adjustments. Such additional License Fee shall be
               payable within thirty (30) days after the end of the calendar
               year in which such increase in production capacity of such
               Licensed Plant occurs. Incremental License Fees for increased
               production capacity in any Licensed Plant shall not be due if the
               increased production capacity is the result of the initial use of
               Licensee Patent Rights or Licensee Technical information. The
               total cumulative incremental capacity adjustments under each Site
               License Agreement will be limited to 50 percent of the initial
               maximum daily capacity under such Agreement.

         D.    Upon payment of all fees due under the Site License Agreement for
               each Licensed Plant under this Section II, Licensee shall be
               deemed to have acquired a fully paid license for such Licensed
               Plant up to the original maximum daily design capacity or any
               adjusted daily design capacity made under the provisions of
               Section II.B. above. Any additional incremental increases in the
               Licensed Plant capacity will be subject to additional License
               Fees as calculated under incremental adjustments pursuant to this
               Section II.

III.  For each Site License Agreement executed under this Agreement for a
      Licensed Plant with a maximum daily design capacity, as defined in the
      Process Design Package, equal to or more than 30,000 barrels but less than
      nominally 180,000 barrels of Synthetic Product per day, Licensee agrees to
      pay License Fees to Licensor as follows.

         A.    PREPAID LICENSE FEE.

               1. Licensee agrees to pay Licensor a one-time, prepaid License
               Fee calculated in accordance with the following formula:

               License Fee = "C" x 350 x 7.5 x "R" x .50 wherein:

                  "C" =    the maximum daily design capacity, as defined by the
                           Process Design Package, of such Licensed Plant to
                           produce Marketable Products measured in Barrels of
                           Synthetic Product per day for
<PAGE>

                           which such Licensed Plant is originally designed and
                           constructed, and

                  "R" =    the Royalty Rate.

               and payable in installments as follows:

                  (i)    20% within thirty (30) days after the execution of the
                         Site License Agreement for such Licensed Plant;

                  (ii)   30% within thirty (30) days after delivery of the
                         Process Design Package or within one hundred twenty
                         (120) days after the execution of the Site License
                         Agreement for such Licensed Plant, whichever first
                         occurs;

                  (iii)  20% within thirty (30) days after the commencement of
                         field construction move-in;

                  (iv)   30% within one-hundred and twenty (120) days after the
                         Start-Up Date of the Licensed Plant or a successful
                         Performance Test as specified in the Process Guarantee
                         and Performance Test Agreement, whichever first occurs.

               2. Notwithstanding any other provision of this Agreement,
               payments made by Licensee to Licensor under Section 5.01 of this
               Agreement and Section 5 of Amendment No. 1 to Volume License
               Agreement between Licensee and Licensor dated October 11, 2000,
               shall be credited against the License Fee payments due by
               Licensee to Licensor under Section III.A.1. at the rate of up to
               50%, such that the Licensor shall receive a cash payment of at
               least 50% of the scheduled installment payment under Section
               III.A.1.

               3. In the event the actual production capacity of any Licensed
               Plant for which a prepaid License Fee has been paid under Section
               III.A. above is determined to have exceeded the original maximum
               daily design capacity established in its Site License Agreement
               by more than five percent (5%) or by more than 500 barrels per
               day, at any time after the Start-up Date, Licensee shall pay
               Licensor an additional License Fee, on a prepaid basis, equal to
               the difference between (a) the prepaid License Fee as would have
               been calculated with the higher production capacity for such
               Licensed Plant substituted for "C" in the calculation method set
               forth in II.A. above, and (b) the License Fee as would have been
               calculated for such Licensed Plant by the method set forth in
               Section III.A. above using the original maximum daily design
               capacity established in each Site License Agreement. Such
               additional License Fee shall be payable within thirty (30) days
               after the end of the calendar year in which such increase in
               production capacity of such Licensed Plant occurs. Incremental
               License Fees for increased production capacity in any Licensed
<PAGE>

               Plant shall not be due if the increased production capacity is
               the result of the initial use of Licensee Patent Rights or
               Licensee Technical information. The total cumulative incremental
               capacity adjustments under each Site License Agreement will be
               limited to 50 percent of the initial maximum daily capacity under
               such Agreement.

         B.    RUNNING ROYALTY LICENSE FEES.

               1. In addition to the prepaid License Fee payable by Licensee to
                  Licensor in accordance with Paragraph A above, Licensee agrees
                  to pay Licensor, on or before thirty (30) days after the end
                  of each calendar month, a monthly running royalty license fee
                  based on the actual operation of the Licensed Plant and
                  calculated in accordance with the following formula:

                  Monthly Running Royalty License Fee =
                     "MP" x ("R" x .50) x "BLS"

                  wherein:

                     "MP" =   the total monthly production in Barrels of
                              Synthetic Product during a calendar quarter as
                              measured in a manner specified in the Process
                              Design Package,

                     "R" =    the Royalty Rate, and

                     "BLS" =  the factor equal to (a) the BLS Index for the
                              calendar year in which the payment is being made
                              divided by (b) the BLS Index applicable as of the
                              Effective Date of the Master License Agreement.

IV.   For each Site License Agreement executed under this Agreement for a Large
      Licensed Plant, Licensee agrees to pay License Fees to Licensor as
      follows:

      1.    FIRST PHASE

            A.    PREPAID LICENSE FEE

                  25% of the Prepaid License Fee for the first nominal 90,000
                  barrels per day of a Large Licensed Plant ("First Phase") will
                  be paid in accordance with the installment payment schedule
                  set forth in Section III.A. above

                  AND
<PAGE>

            B.    RUNNING ROYALTY LICENSE FEES

                  The remaining License Fee in respect to the First Phase of a
                  Large Licensed Plant, will be paid, on or before thirty (30)
                  days after the end of each calendar month, as a running
                  royalty license fee ("First Phase Running Royalty License
                  Fee") per barrel of actual production of Marketable Products
                  for the life of the project. The First Phase Running Royalty
                  License Fee rate, will be equal to 75% of the standard Royalty
                  Rate for a Licensed Plant current at the time of execution of
                  the Site License Agreement and escalated annually thereafter
                  based upon the Bureau of Labor Statistics published inflation
                  index, calculated as follows:

                  FirstPhase Running Royalty License Fee =
                      "MP x ("R" x 0.75) x "BLS"

                  Wherein:

                     "QP" =   total monthly production in Barrels of Marketable
                              Products during a calendar month

                     "R" =    the Royalty Rate

                     "BLS" =  the factor equal to (a) the BLS index for the
                              calendar year in which the payment is being made
                              divided by (b) the BLS Index applicable as of the
                              Effective Date of the Master License Agreement.

      2.    SECOND PHASE

            For the second nominal 90,000 barrels per day minimum or more for
            the Large Licensed Plant under the same Site License Agreement
            referenced above ("Second Phase") that will be included in a
            combined design with the First Phase as a single project for
            purposes of preparation of the Process Design Package, with the
            Second Phase constructed either concurrently with the First Phase or
            in a separate consecutive period starting no more than 1 year
            following the start of construction of the First Phase, the License
            Fee associated with the Second Phase of the Large Licensed Plant
            shall be paid as follows:

            A.    PREPAID LICENSE FEES

                  25% of the Prepaid License Fee for the Second Phase will be
                  payable in installments as follows:

                  (i) 50% at the closing of the financing on the First Phase
                  with respect to a Large Licensed Plant covered by a Site
                  License (Financial Closing)

                  (ii) 20% within thirty (30) days after the commencement of
                  field construction move-in; and
<PAGE>

                  (iii) 30% at the satisfactory Performance Test of the Second
                  Phase of the Large Licensed Plant.

                  AND

            B.    RUNNING ROYALTY LICENSE FEES

                  The remaining License Fee in respect to the Second Phase of
                  the Large Licensed Plant, will be paid, on or before thirty
                  (30) days after the end of each calendar month, as a running
                  royalty license fee ("Second Phase Running Royalty License
                  Fee") per barrel of actual production of Marketable Products
                  for the life of the project. The Second Phase Running Royalty
                  License Fee rate, will be equal to 50% of the standard Royalty
                  Rate for the Licensed Plant current at the time of execution
                  of the Site License Agreement and escalated annually
                  thereafter based upon the Bureau of Labor Statistics published
                  inflation index, calculated as follows:

                  Second Phase Running Royalty License Fee =
                     "MP x ("R" x 0.50) x "BLS"

                  Wherein:

                     "MP" =   total monthly production in Barrels of Marketable
                              Products during a calendar month

                     "R" =    the Royalty Rate

                     "BLS" =  the factor equal to (a) the BLS index for the
                              calendar year in which the payment is being made
                              divided by (b) the BLS Index applicable as of the
                              Effective Date of the Master License Agreement.

      3.    Accumulated credits, if any, to which Licensee is entitled against
            the License Fee under the Site License may be applied at Financial
            Closing and any remaining credits may be applied the thirty (30)
            days after commencement of field construction move-in.




V.    All payments required hereunder shall include a statement showing the
      details supporting the calculation of the License Fees being paid.
      Licensee shall keep accurate and complete records of all natural gas
      feedstock processed (volume and composition) and all Synthetic Product
      produced at and either used internally within or removed from each
      Licensed Plant to enable verification of statements and
<PAGE>

      payments rendered to Licensor hereunder. Licensee agrees to permit
      Licensor, at Licensor's expense, to inspect such records on reasonable
      notice and at reasonable intervals during normal business hours to verify
      the license fees paid and payable under this Agreement.

VI.   If the Licensee can not achieve financing on commercially reasonable terms
      for the Licensed Plant or if the project is terminated for any reason
      prior to such time, Licensee shall retain 25% of the License Fee payments
      made to Licensor for the project up to that date and the remaining 75%
      shall be credited to any future Licensed Plant that is initiated within 15
      years from the Effective Dates of the Master License Agreement.