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                                                                REDACTED VERSION

                                  EXHIBIT 10.11

                                       TO

                         LIGHT SCIENCES ONCOLOGY, INC.'S

                       REGISTRATION STATEMENT ON FORM S-1

                                 INITIALLY FILED

                                 APRIL 21, 2006

                           REGISTRATION NO. 333-133474

"[ * ]" = omitted, confidential material, which material has been separately
          filed with the Securities and Exchange Commission pursuant to a
          request for confidential treatment.

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                           EXCLUSIVE LICENSE AGREEMENT

                           DATED AS OF OCTOBER 5, 2005

                                     BETWEEN

                           LIGHT SCIENCES CORPORATION

                                       AND

                          LIGHT SCIENCES ONCOLOGY, INC.

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                           EXCLUSIVE LICENSE AGREEMENT

     THIS EXCLUSIVE LICENSE AGREEMENT (this "Agreement") is effective as of
October 5, 2005 (the "Effective Date") by and between Light Sciences
Corporation, a Washington corporation ("LSC"), and Light Sciences Oncology,
Inc., a Washington corporation ("LSO").

     WHEREAS, LSC owns or controls certain technology and intellectual property
rights relating to the treatment, diagnosis and monitoring of cancer and may in
the future own or control additional technology and intellectual property
rights;

     WHEREAS, LSO desires to enter an exclusive license with LSC to
commercialize such technology in the Field of Use (as defined below);

     WHEREAS, concurrent with the execution of this Agreement, LSC and LSO shall
enter into a separate sublicense agreement with respect to the LSC Excluded
Technology (as defined below) and LSO shall not obtain any rights to the LSC
Excluded Technology pursuant to this Agreement;

     WHEREAS, LSC has created certain subsidiaries and may create additional
subsidiaries, in its sole and complete discretion, which have licensed or will
license the LSC Licensed Technology (as defined below) from LSC in order to
pursue research and development efforts in separate fields of use other than the
Field of Use (such subsidiaries being referred to as the "Additional LSC Subs");
and

     WHEREAS, LSO and the Additional LSC Subs desire to provide for the control
and sharing of costs related to the prosecution and maintenance of patents
included in the LSC Licensed Technology and the prosecution of any infringement
actions related thereto;

     NOW, THEREFORE, in consideration of the covenants and obligations
hereinafter set forth, the parties hereto hereby agree as follows:

1.   Definitions.

     1.1. "Abandonment" shall have the meaning set forth in Section 5.3(a).

     1.2. "Additional Licensees" shall mean each Additional LSC Sub and any
other Person who has obtained a license to the LSC Licensed Technology directly
from LSC for use outside the Field of Use and who has a right similar to that of
LSO to participate in the prosecution, maintenance and enforcement of the LSC
Licensed Technology. A Person shall not be deemed to be an Additional Licensee
with respect to particular LSC Licensed Technology if the Person (including an
Additional LSC Sub) does not have an exclusive license to the particular LSC
Licensed Technology or rights with respect to the prosecution, maintenance and
enforcement of the particular LSC Licensed Technology that are similar to LSO's
rights set forth in Section 5. For example, a Person who did not license a
particular patent (or subsequently had the patent removed from the definition of
"LSC Patents" that it was licensing) would not be an

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"Additional Licensee" for purposes of the notices and other rights and
activities described in Section 5 for "Additional Licensees" with respect to the
patent.

     1.3. "Additional LSC Subs" shall have the meaning set forth in the
Recitals.

     1.4. "Additional LSC Sub License Agreement" shall have the meaning set
forth in Section 7.7.

     1.5. "Affiliate" with respect to any Person shall mean entities that are
controlled by or are under common control of such Person; provided, however,
that the Additional LSC Subs, LSC and LSO shall be deemed not to be Affiliates
of each other or be deemed to be controlled by, controlling or under common
control with each other, for the purposes of this Agreement. For purposes of
this definition, "control" shall mean that a Person owns or controls fifty
percent (50%) or more of the voting securities of an entity or of an interest in
the assets, profits or earnings of an entity.

     1.6. "Bankruptcy Code" shall have the meaning set forth in Section 8.2.

     1.7. "Bona Fide Dispute" shall have the meaning set forth in Section 5.2.

     1.8. "Confidential Information" shall have the meaning set forth in Section
6.1.

     1.9. "Damages" shall mean any and all claims, suits, losses, damages,
costs, fees, and expenses, including reasonable attorney fees and litigation
costs.

     1.10. "Dispute" shall have the meaning set forth in Section 11.3.

     1.11. "Field of Use" shall mean the diagnosis, prophylaxis, treatment and
monitoring in humans or animals of tumors, malignant disease, cancers, [ * ].
The Field of Use does not include [ * ].

     1.12. "Governmental Authority" means any U.S. Federal, state, foreign or
local government or any court, tribunal, administrative agency or commission or
other governmental or regulatory authority, body or agency, including any
self-regulatory organization.

     1.13. "Infringement Parties in Interest" shall have the meaning set forth
in Section 5.4(a).

     1.14. "License" shall have the meaning sent forth in Section 2.

     1.15. "Licensed Products" shall mean any products which would infringe the
claims of the LSC Patents, LSC Patent Applications or LSC Trademarks if there
were no license between LSC and LSO, or which involve the use of LSC Know-How.

     1.16. "Liens" means any lien, pledge, mortgage, security interest, claim,
lease, charge,

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option, right of first refusal or first offer, transfer restriction, voting
requirement or any other encumbrance, restriction or limitation, other than any
the rights granted contemporaneously or subsequently to the Additional LSC Subs
or other Additional Licensees.

     1.17. "LSC Event of Default" shall have the meaning set forth in Section
8.3(a).

     1.18. "LSC Excluded Technology" shall mean any and all rights licensed to
LSC under the License and Supply Agreement dated as of April 28, 2000 by and
among Nippon Petrochemicals Co., Ltd., Meiji Seika Kaisha, Ltd, and LSC, as
amended from time to time.

     1.19. "LSC Improvements" shall mean any new or useful invention, process or
improvement, patentable or unpatentable, relating to or arising from the LSC
Patents or LSC Patent Applications, as the case may be, conceived or first
reduced to practice or demonstrated to have utility by LSC during the Term.

     1.20. "LSC Know-How" shall mean any invention, discovery, know-how, data,
formulae, information, composition, process, trade secret, equipment and other
subject matter relating to the LSC Licensed Technology that is (a) owned or
controlled by LSC during the Term and (b) necessary or useful for the research,
development, manufacture or commercialization of any Licensed Product in the
Field of Use. LSC Know-How does not include LSC Excluded Technology.

     1.21. "LSC Licensed Technology" shall mean the LSC Patents, LSC Patent
Applications, LSC Know-How and LSC Trademarks; provided, however, in no case
shall the LSC Licensed Technology include any LSC Excluded Technology, which
shall be subject to a separate agreement.

     1.22. "LSC Patents" shall mean the patents listed in Appendix A, as well as
foreign counterparts thereof, patents issuing from LSC Patent Applications,
patents that are in-licensed or controlled by LSC during the Term, and
reexaminations, reissues, patents of addition and extensions of the foregoing
(including, without limitation, any LSC Improvements relating to the foregoing).
LSC Patents do not include LSC Excluded Technology or patents that have been
removed from the definition pursuant to Section 5.2 or 5.3(c) due to the action
or inaction of LSO.

     1.23. "LSC Patent Applications" shall mean (a) the patent applications
listed in Appendix B and (b) all patent applications that cover inventions or
discoveries that are made, developed, conceived, first reduced to practice,
in-licensed or controlled by LSC during the Term, as well as continuations,
divisionals, continuations-in-part, and foreign counterparts of each of the
foregoing subsections (a) and (b) (including, without limitation, any LSC
Improvements relating to the foregoing). LSC Patent Applications do not include
LSC Excluded Technology or patent applications that have been removed from the
definition pursuant to Section 5.2 or 5.3(c) due to the action or inaction of
LSO.

     1.24. "LSC Trademarks" shall mean the trademarks and trademark applications
listed in Appendix C.

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     1.25. "LSO Patents" shall mean all patents and patent applications covering
inventions that arise from the License to the extent such inventions are made,
developed, conceived or first reduced to practice by LSO alone or jointly with
others during the Term (but only to the extent of LSO's rights in same),
including all divisionals, continuations, and continuations-in-part of such
patent applications as well as reexaminations, reissues, patents of addition,
extensions and any foreign counterparts thereof.

     1.26. "LSO Technology" shall mean the LSO Patents and, to the extent not
covered by the LSO Patents, any inventions, discoveries, know-how, data,
formulae, information, compositions, processes, trade secrets, equipment and
other subject matter relating to or derived from the exercise of the License, to
the extent such inventions are conceived, discovered or made by LSO alone or
jointly with others (but only to the extent of LSO's rights in same) during the
Term.

     1.27. "Net Sales" shall mean the aggregate amounts invoiced each year by
LSO and its Affiliates and sublicensees from sales of Licensed Products to
unrelated third parties (i.e., distributors, agents, wholesalers, customers or
reimbursement organizations, as the case may be), less the following deductions
related to the sales: [ * ].

     1.28. "Person" shall mean a natural person, partnership (general or
limited), corporation, joint venture, business trust, limited liability company,
cooperative, association or other form of business organization, trust, estate
or any other entity, other than a Governmental Authority.

     1.29. "Pro Rata Percentage" shall mean the percentage obtained by
multiplying [ * ] by the fraction with a numerator equal to [ * ] and a
denominator equal to [ * ]. The Pro Rata Percentage shall be recalculated
whenever an Additional LSC Sub or Additional Licensee is created [ * ] for
purposes of the calculation in the preceding sentence, which recalculated Pro
Rata Percentage shall be [ * ]. By way of example, if on the date hereof [ * ].

     1.30. "Prosecution Costs" shall have the meaning set forth in Section 5.2.

     1.31 "Right of First Refusal and Co-Sale Agreement" shall mean the Right of
First Refusal and Co-Sale Agreement dated October 6, 2005, by and among LSO, LSC
and each of the persons and entities identified as parties therein.

     1.32. "Royalty Period" shall mean for each Licensed Product, on a
country-by-country basis, the later of (a) the last to expire of any patents
included in the LSC Patents [ * ] or (b) ten (10) years after first commercial
sale to a third party [ * ] of any Licensed Product in the country [ * ].

     1.33 "Term" shall have the meaning set forth in Section 8.1.

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     1.34 "Threshold Amount" shall mean [ * ].

2.   License.

     (a) LSC Licensed Technology. LSC hereby grants to LSO an exclusive (even as
to LSC), perpetual, worldwide license, with right to assign or sublicense, to:
(a) use the LSC Licensed Technology in the Field of Use; (b) make and have made
Licensed Products within the Field of Use; and (c) sell, have sold, offer to
sell, import, export or otherwise distribute Licensed Products for use within
the Field of Use (the "License"); provided, however, the duration of the License
may only be terminated if the conditions in Section 5.2, 8 or 9.2 occur.

     (b) Reservation of Rights. LSC reserves for itself a nonexclusive,
nontransferable right to use the LSC Licensed Technology in the Field of Use
solely for noncommercial research and development purposes.

3.   Consideration; Taxes.

     3.1. Royalty. As consideration for the License granted by LSC to LSO under
Section 2, LSO shall pay a royalty to LSC in an amount equal to [ * ] of Net
Sales of Licensed Products during the Royalty Period. At the end of the Royalty
Period for each Licensed Product, no further royalties shall accrue and the
License shall become fully paid-up and royalty-free.

     3.2. Reports and Payments. LSO shall provide written reports and payments
to LSC within [ * ] days after the close of each calendar quarter during the
Term. These reports shall show for such calendar quarter sales by LSO and any
sublicensees of Licensed Products, details of the quantities of each type of
Licensed Product sold in each country, Net Sales for each Licensed Product, the
form of revenue received and the royalties due LSC thereon. Concurrently with
the making of each such report, LSO shall make payment to LSC in U.S. dollars of
amounts payable for the period covered by such report. Where Net Sales is in a
currency other than U.S. dollars, conversion of Net Sales into U.S. dollars
shall be at the exchange rate prevailing at Citicorp N.A. on the last business
day of the quarter to which the payment pertains.

     3.3. LSO Records. LSO shall keep clear, accurate and complete records, for
a period of at least three (3) years, for each reporting period in which sales
occur showing the sales or other disposition of Licensed Products in sufficient
detail to enable verification of amounts payable pursuant to Section 3.1.
Following reasonable notice, LSC shall have the right, at LSC's sole expense, to
have LSO's books and records examined during regular business hours, but not
more than once a year, by an independent accounting firm reasonably acceptable
to LSO, which firm is bound in confidence to disclose only evidence of
noncompliance by LSO with respect to the calculation of royalties due hereunder.
In the event LSO has underpaid LSC, LSO shall pay the amount of such
underpayment immediately and, to the extent such underpayment is more than [ * ]
for the audited period, shall reimburse LSC for the reasonable expense of the
audit. If LSO has overpaid LSC, such overpayment shall be immediately refunded
by LSC.

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     3.4. LSC Records. LSC shall keep clear, accurate and complete records, for
a period of at least three (3) years, for each reporting period which LSC has
submitted statements of account to LSO of costs and expenses which are
reimbursable under this Agreement, in sufficient detail to enable verification
of amounts payable. Following reasonable notice, LSO shall have the right, at
LSO's sole expense, to have LSC books and records examined during regular
business hours, but not more than once a year, by an independent accounting firm
reasonably acceptable to LSC, which firm is bound in confidence to disclose only
evidence of noncompliance of LSC with respect to the calculation of reimbursable
expenses. In the event LSC has overcharged LSO, LSO shall pay immediately the
amount of such overcharge that has been paid by LSO and, to the extent such
overcharge is more than [ * ] for the audited period, reimburse LSO for the
expense of the audit. If LSO has underpaid LSC, the amount of such underpayment
shall be immediately paid to LSC.

     3.5. Confidentiality of Reports and Records. A party's information that is
set forth in (a) the reports required by Section 3.2 and (b) the records subject
to examination under Sections 3.3 and 3.4, shall be subject to Section 6 hereof
and maintained in confidence by the other party and its independent accounting
firm performing the audit and shall not be used for any purpose other than
verification of the performance of obligations hereunder and the enforcement
thereof.

     3.6. Taxes. LSO is solely responsible for the payment of any taxes
(including withholding, sales or use taxes, intangible taxes and property taxes)
resulting from the payment of royalties to LSC hereunder, other than any taxes
assessed by any jurisdiction which are based on the income of LSC. LSO agrees to
hold harmless LSC from all claims and liability arising from LSO's failure to
report or pay any such taxes.

     3.7 Value of Know-How. LSO acknowledges that the LSC Know-How constitutes
valuable and substantial trade secrets and know-how of LSC. The parties
acknowledge and agree that, for their mutual convenience and after considering
other alternatives, the payments to LSC set forth in this Agreement, including
the structure and timing of royalty payments, are an appropriate and mutually
convenient way of compensating LSC.

4.   Ownership of Intellectual Property; Use of LSC Trademarks/Names/Patent
     Numbers.

     4.1. LSO Technology. Any and all intellectual property created, generated
or developed by or on behalf of LSO during the Term from the exercise of the
License shall vest in and be owned by LSO and shall be considered to be part of
LSO Technology.

     4.2. LSC Licensed Technology. Subject to the License, any and all
intellectual property created, generated or developed by or on behalf of LSC
during the Term shall vest in and be owned by LSC and, if necessary or useful in
the Field of Use, shall be included in the LSC Licensed Technology.

     4.3. Joint Inventions. Any intellectual property arising or resulting from
the inventive

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work by one or more employees of LSC and LSO (and any other Persons), as to
which the employees would be inventors under the patent laws of the United
States, shall be jointly owned by the parties (each party having an undivided
interest therein), and all of LSC's rights and interests therein shall be
subject to the License. The laws of the United States with respect to joint
ownership of inventions shall be applied in all jurisdictions of the world to
the parties' joint ownership interests.

     4.4. Use of LSC Trademarks. The License includes the exclusive right to use
the LSC Trademarks in advertising, labeling, promoting and selling Licensed
Products in the Field of Use. The nature and quality of all Licensed Products
sold by LSO under the LSC Trademarks shall be of a quality and nature comparable
to similar products sold by other reputable medical device, pharmaceutical or
biotechnology companies. To facilitate this quality control provision, LSO
shall, upon reasonable request, permit LSC to inspect at LSO's facility or its
manufacturer's facility any Licensed Products to be sold by LSO under the LSC
Trademarks. In addition, LSO shall, upon reasonable request, provide to LSC
samples of any advertising or promotional materials published by LSO that
display the LSC Trademarks. LSO shall use the LSC Trademarks with such trademark
designations as are reasonably necessary to protect the status of the LSC
Trademarks as trademarks.

     4.5. Use of Name. Except as provided by this Agreement, neither party shall
use the trademark, indicia or name of the other party on any advertising,
promotional or labeling of Licensed Product without the written approval of the
other party, which approval shall not be unreasonably withheld, conditioned or
delayed.

     4.6. Marking. LSO shall mark all Licensed Products with the applicable
patent and patent application number(s) in accordance with all applicable local,
state and federal rules and regulations.

5.   Patent Maintenance and Enforcement.

     5.1. Prosecution and Maintenance. Except upon Abandonment, LSC shall be
responsible for all filing, prosecution and maintenance of the LSC Patents and
LSC Patent Applications in every jurisdiction worldwide and shall be responsible
for determining strategy with respect thereto. LSC shall act in good faith and
in a commercially reasonable and diligent manner with respect to the filing,
prosecution and maintenance of the LSC Patents and LSC Patent Applications. LSC
shall give due respect to LSO's position with respect to the filing, prosecution
and maintenance of the LSC Patents and LSC Patent Applications and LSC may, in
its sole discretion, also give due respect to the Additional Licensees'
positions with respect thereto. LSC shall keep LSO promptly and fully informed
of the course of patent filings, prosecution and other proceedings, including
providing to LSO copies of substantive communications, search reports and third
party observations submitted to or received from patent offices, all of which
shall be provided to LSO in sufficient time for LSO to review and provide
comments to LSC prior to LSC taking any action or making any filing with any
patent offices. LSO shall have the right to review proposed filings, pending
applications, patents and other proceedings and make recommendations to LSC
concerning them and their conduct, which LSC shall consider in good faith and
take into account in its filing, prosecution and maintenance of the LSC Patents
and LSC Patent Applications. LSO shall be responsible for its own expenses in

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providing such patent consultation to LSC. Any input provided by LSO to LSC with
respect to the filing, prosecution and maintenance of the LSC Patents and LSC
Patent Applications shall be deemed to be the Confidential Information of LSC.

     5.2. Allocation of Expenses; Penalty for Nonpayment. LSO shall pay the Pro
Rata Percentage of the out-of-pocket costs and expenses (including attorneys'
fees) reasonably incurred by LSC after the Effective Date in filing, prosecuting
and maintaining the LSC Patents and LSC Patent Applications (the "Prosecution
Fees"); provided, however, that LSO may elect, upon [ * ] days prior written
notice to LSC and the Additional Licensees, [ * ].

     5.3. Abandonment by LSC.

          (a) Notice. In the event LSC decides not to file or continue the
prosecution or maintenance of a particular patent or patent application included
in the definition of the LSC Patents and LSC Patent Applications in a particular
jurisdiction or every jurisdiction (an "Abandonment"), LSC shall promptly
provide notice (which notice shall include the basis for such action in
reasonable detail) to LSO (and to any Additional Licensees) at least [ * ] days
prior to the date which any filing or payment is required to be made in order to
preserve the rights to such patent or patent applications.

          (b) Election by LSO. LSO shall notify LSC and all Additional Licensees
within [ * ] days of receiving LSC's Abandonment notice pursuant to Section
5.3(a) whether LSO desires to pursue the filing, prosecution or maintenance of
the patents or patent applications subject to Abandonment. If LSO gives such
notice that it desires to pursue such filing, prosecution or maintenance, LSO
shall assume and be assigned and allowed to exercise all of LSC's rights and
obligations under Sections 5.1 and 5.2 in pursuing the patents or patent
applications subject to Abandonment, including filing, prosecution and
maintenance in the name of LSC with reimbursement of Prosecution Fees as set
forth in Section 5.2. In the event LSO does not give such notice or notifies LSC
and the Additional Licensees that it is not interested in pursuing such patents
or patent applications, any Additional Licensee who has given notice of its
desire to pursue such patents or patent applications within [ * ] days of LSC's
notice of Abandonment pursuant to Section 5.3(a) shall be entitled to assume and
be assigned and allowed to exercise all of LSC's rights and obligations under
Sections 5.1 and 5.2 with respect to such Abandonment; if more than one
Additional Licensee has given such notice, LSC shall promptly designate one of
the Additional Licensees to have such rights and obligations based on LSC's
judgment of the Additional Licensee to whom such patent or patent application
has the greatest value in its licensed field of use.

          (c) Assignment to LSO or an Additional Licensee. If LSO has given
notice of its desire to pursue the patents or patent applications pursuant to
Section 5.3(b) and no Additional Licensees have given notice to LSO, LSC and the
other Additional Licensees within [ * ] days of receiving LSC's Abandonment
notice pursuant to Section 5.3(a) of its desire, to pursue the patents or patent
applications, LSO may elect to assume all future responsibility with respect to
the patents or patent applications subject to Abandonment (including
responsibility for

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all future accruing fees and expenses related thereto) and be assigned such
patents or patent applications, in which event such patents or patent
applications shall be removed from the definition of "LSC Patents" or "LSC
Patent Applications" (and not be royalty bearing) and LSC shall cause such
patents or patent applications to be removed from the licenses granted by LSC to
the Additional Licensees. If LSO has not given notice of its desire to pursue
the patents or patent applications and only one Additional Licensees has so
given notice of its desire to pursue the patents or patent applications, such
Additional Licensee may elect to assume all future responsibility with respect
to the patents or patent applications subject to Abandonment (including
responsibility for all future accruing fees and expenses related thereto) and be
assigned such patents or patent applications, in which event such patents or
patent applications shall be removed from the definition of "LSC Patents" or
"LSC Patent Applications" and LSC shall cause such patents or patent
applications to be removed from the licenses granted by LSC to all other
Additional Licensees.

          (d) Cooperation. In the event LSO undertakes responsibility with
respect to any filing, prosecution or maintenance of abandoned patents or patent
applications, LSC shall cooperate with and assist LSO with the filing,
prosecution or maintenance and provide LSO with all files, correspondence and
other records in its possession related to the filing, prosecution or
maintenance thereof; provided, however, that LSO shall reimburse LSC for all
reasonable expenses incurred by LSC in providing such cooperation and LSC shall
cause all other Additional Licensees to reimburse LSO for their Pro Rata
Percentage of such reimbursement.

          (e) Abandonment by LSO. In the event that LSO decides not to file or
continue the prosecution or maintenance of any such patent or patent application
after initially making such election, LSO shall promptly notify LSC (and any
Additional Licensee) at least [ * ] days prior to the date which any filing or
payment is required to be made in order to preserve the rights to such patent or
patent applications; provided, however, if LSO has received less than [ * ] days
prior notice, LSO shall provide notice to LSC as soon as practicable.

     5.4. Infringement of Patents by a Third Party.

          (a) Notice. In the event that any infringement of a LSC Patent by a
third party shall come to the attention of LSO or LSC, then such party shall
promptly notify the other party and each Additional Licensee of the nature and
evidence of such infringement and whether such infringement appears to have
occurred in any fields to which the LSC Patent has been licensed to LSO or any
Additional Licensee. LSC shall notify LSO and each Additional Licensee within
[ * ] days of giving or receiving such infringement notice (including an
infringement notice from an Additional Licensee that has been given in
accordance with this Section 5.4(a)) whether or not it intends to bring a patent
infringement action against the third party and the licensed field (i.e., LSO's
and/or any Additional Licensees') in which such infringement appears to have
occurred (LSO and/or any Additional Licensees in whose licensed field the
infringement has occurred and who are identified by LSC or who have given notice
to the other Additional Licensees, LSO and LSC of such infringement in their
licensed fields not later than [ * ]

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days after the date that LSC's notice is due is hereafter referred to as the
"Infringement Parties in Interest").

          (b) LSC Action. If LSC gives such notice of its intention to bring
such an infringement action, LSC shall bring such action within the next [ * ].
Any recovery by LSC in such infringement action shall [ * ].

          (c) Licensee Action. If LSC gives notice of its intention not to bring
such an infringement action or fails to give notice as required in Section
5.4(a), the Infringement Parties in Interest may elect to have all future
responsibility with respect to bringing such infringement action, (and be
responsible for all fees and expenses related thereto [ * ]; provided, however,
if LSO and at least one Additional Licensee are electing Infringement Parties in
Interest, LSO shall negotiate in good faith a joint agreement among the electing
Infringement Parties in Interest with respect to such infringement action and
the sharing of expenses and monetary awards relating thereto. Such joint
agreement shall be submitted to review by LSC, which shall have [ * ].

          (d) Dispute Regarding Action. If the electing Infringement Parties in
Interest are not able to mutually agree on bringing the infringement action
[ * ]; provided, however, if any Infringement Party in Interest requests, [ * ]
by the Infringement Parties in Interest electing to [ * ].

          (e) Cooperation of LSC. In the event LSO [ * ] assist LSO (and any
Additional Licensees, as applicable) and execute all necessary and proper
documents and take such actions as shall be appropriate in connection with
[ * ].

          (f) Cooperation of LSO. LSO shall cooperate with and assist LSC or
Infringement Parties in Interest with regard to any such infringement action and
execute all necessary and proper documents and take such actions as shall be
appropriate in connection with such infringement action.

     5.5. LSO Election. Notwithstanding the foregoing, LSO shall be entitled to
assume full responsibility for filing and all prosecution, maintenance and
enforcement (including bringing any infringement action and retaining any
recoveries therefrom) of any particular LSC Patent Application or LSC Patent in
the name of LSC and shall bear all costs related thereto, provided that LSO (a)
notifies LSC and obtain LSC's written consent to such assumption and (b)
notifies each Additional Licensee known to LSO in writing and no Additional
Licensee objects to such assumption within [ * ] days of receipt of such notice.
If any Additional Licensee objects to such assumption, LSO shall discuss in good
faith such objections in an attempt to reach a mutually acceptable agreement
with any objecting Additional Licensees.

     5.6. Misappropriation of Trade Secret; Infringement of Trademark. In the
event there has been a misappropriation of a trade secret or infringement of a
trademark included in the LSC

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Licensed Technology, an action for misappropriation of the trade secret or
infringement of the trademark shall be handled in the same way as, and the
parties shall proceed and have the same rights as, set forth in Section 5.4 with
respect to infringement of a LSC Patent, and notices and other rights described
in Section 5.4 shall be given to those Additional Licensees who have exclusive
license rights to the trade secret or trademark and rights with respect to
enforcement that are similar to LSO's rights.

     5.7 LSO Election in the Event of LSC Change of Control. In the event of a
LSC Change of Control with any person or entity other than an Industry Operating
Company occurring prior to an initial public offering of LSC securities to the
general public, LSO shall be entitled upon written notice given to LSC and the
Additional Licensees within [ * ] days after the closing of such LSC Change of
Control (the "Exercise Notice") to assume and exercise any or all of LSC's
rights and responsibilities under this Agreement with respect to the filing,
prosecution, maintenance or enforcement of any of the LSC Licensed Technology
under this Section 5 (unless the exercise of the right to give the Exercise
Notice is waived in writing by holders of a majority of the Series A Preferred
Stock of LSO). The assumption of rights under this Section 5.7 shall become
effective immediately upon receipt of the Exercise Notice by LSC, and LSC shall
promptly cooperate with LSO in all respects necessary to give effect to the
Exercise Notice in accordance with this Agreement. After such a LSC Change of
Control and prior to the delivery of the Exercise Notice, if same shall occur,
LSC shall take all necessary action to maintain the status quo of the LSC
Licensed Technology and shall not, by action or inaction, permit any patent
rights in the LSC Licensed Technology to become abandoned or adversely affected
in any respect. However, any such election shall not modify the financial
arrangements or obligations of the parties under this Agreement or under any
Additional LSC Sub License Agreement (e.g., each party and each Additional
Licensee shall continue to be obligated financially to the same extent as if LSO
had not assumed LSC's rights and responsibilities pursuant to this Section 5.7).
If LSO does not elect to assume any such rights or responsibilities within such
[ * ]-day period, then the Additional Licensees shall have the right to elect to
assume and exercise such rights and responsibilities of LSC in the order of
preference agreed upon by LSC and the Additional Licensees by giving written
notice to LSC and LSO. If the Additional Licensees elect to assume and exercise
such rights and responsibilities, the financial arrangements or obligations of
the parties under this Agreement or any Additional LSC Sublicense Agreement
shall remain unchanged. The failure of LSO to exercise its right to assume and
exercise any or all of LSC's rights and responsibilities for the filing,
prosecution, maintenance or enforcement of any LSC Licensed Technology under
this Section 5.7 shall not affect the License or any of LSO's other rights under
this Agreement. LSO shall not be entitled to give an Exercise Notice with
respect to any LSC Change of Control occurring after the first such LSC Change
of Control following the date of this Agreement. Capitalized terms used in this
Section 5.7 and not defined in this Agreement shall have the meaning set forth
in the Right of First Refusal and Co-Sale Agreement.

     5.8 Patent Term Extension. The parties shall cooperate in seeking any
available extensions of the terms of the patents included in the LSC Patents,
including (a) advising each other in a timely manner of any action by a
Governmental Authority that is pertinent to any

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<PAGE>

extension, (b) reasonably supplying each other with all information in its
control pertaining to the extension of the terms of such patents and (c)
cooperating with each other to execute all supporting affidavits or documents
required in connection with the extension of such patents. In connection with
LSO receiving governmental approvals to sell a Licensed Product and at the
request of LSO, LSC shall seek, in accordance with and to the extent permitted
by applicable law, extensions of the terms of such patents designated by LSO
that are related to the Licensed Product.

6.   Confidentiality.

     6.1. Confidential Information. Subject to Section 6.2, "Confidential
Information" shall mean (a) any proprietary or confidential information or
material in tangible form disclosed hereunder that is designated as
"Confidential" at the time it is delivered to the receiving party or (b)
proprietary or confidential information disclosed orally hereunder which is
identified as confidential or proprietary when disclosed and such disclosure of
confidential information is confirmed in writing within [ * ] days by the
disclosing party. Any LSC Know-How included in any assets or associated with any
assets (including, without limitation, contracts, INDs, drug master files and
clinical and regulatory records) assigned by LSC to LSO shall be deemed to be
the Confidential Information of LSO, except to the extent it becomes a matter of
public knowledge without fault on the part of LSC. Each party shall exercise due
care (i.e., at least as much care as it affords its own confidential
information) to prevent unauthorized disclosure or use of Confidential
Information. The obligations of confidentiality and nonuse shall exist for the
Term and a period of [ * ] years thereafter.

     6.2. Exclusions. Confidential Information shall not include information
that the receiving party can establish, through documentary evidence, to:

          (a) have been known by the receiving party prior to communication by
the disclosing party;

          (b) have been a matter of public knowledge at the time of such
disclosure by the disclosing party;

          (c) have become a matter of public knowledge, without fault on the
part of the receiving party, subsequent to disclosure by the disclosing party to
the receiving party; or

          (d) have been disclosed to the receiving party from a third party
lawfully having possession of such Confidential Information without an
obligation of confidentiality to the disclosing party.

     6.3. Permitted Uses/Disclosures. Notwithstanding the provisions of Section
6.1 above, the receiving party may use or disclose Confidential Information of
the disclosing party in connection with the exercise of its rights hereunder
(including commercialization and sublicensing) or the fulfillment of its
obligations and duties hereunder and in prosecuting or defending litigation,
complying with applicable U.S. and international governmental regulations

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<PAGE>

(including, without limitation, regulations of the Securities and Exchange
Commission and the U.S. Food and Drug Administration) and submitting information
to tax or other U.S. and international governmental authorities; provided,
however, if the receiving party is required by law to make any public
disclosures of Confidential Information of the disclosing party, to the extent
it may legally do so, it shall give reasonable advance notice to the disclosing
party of such disclosure to enable the disclosing party to interpose an
objection to such a requirement and shall use its reasonable efforts to secure
confidential treatment of the Confidential Information prior to its disclosure
(whether through protective orders or otherwise).

     6.4. Confidentiality of this Agreement. The terms of this Agreement shall
be deemed to be Confidential Information of both parties and subject to the
provisions of this Section 6, except that either party may disclose the terms of
this Agreement to actual or prospective corporate partners and actual or
prospective investors and other professional advisors without the prior consent
of the other party under appropriate confidentiality provisions.

7.   Representations and Warranties, Disclaimer of Liability; Indemnification;
     Covenants.

     7.1. Representations and Warranties by LSC. LSC represents and warrants to
LSO that:

          (a) it is a corporation duly organized and validly existing under the
laws of the State of Washington and has the requisite power and authority to
execute and deliver this Agreement and to consummate the transactions
contemplated hereby, including the right to grant the rights and licenses
granted herein;

          (b) no consent, approval or authorization of, or declaration or filing
with, any Governmental Authority or Person is required on the part of LSC in
connection with its execution, delivery and performance of this Agreement or the
consummation of the transactions contemplated hereby;

          (c) the execution and delivery of this Agreement and the performance
and consummation of the transactions contemplated hereby have been duly
authorized by all necessary action on the part of LSC, and this Agreement has
been duly executed and delivered by LSC and, subject to the due authorization,
execution and delivery by LSO, constitutes a valid and binding obligation of
LSC, enforceable against LSC in accordance with its terms, except as may be
limited (i) by applicable bankruptcy, insolvency, reorganization or other laws
of general application relating to or affecting the enforcement of creditors'
rights generally; and (ii) by the effect of rules of law governing the
availability of equitable remedies;

          (d) the execution and delivery of this Agreement does not, and the
consummation of the transactions contemplated hereby will not (i) conflict with,
or result in any violation or breach of any provision of the Articles of
Incorporation, by-laws or organizational documents of LSC, (ii) conflict with or
violate any applicable Federal or state statutes, judgments, decrees, laws,
ordinances, rules, regulations, injunctions and orders applicable to LSC or any
of its assets or operations or (iii) result in any violation or breach of,
constitute a default under or conflict with the provisions of any agreement to
which LSC is a party or by which it or any of its properties or assets is
otherwise bound;

<PAGE>

          (e) it has good title to all LSC Licensed Technology, free and clear
of all Liens and is not in default (or, with the giving of notice or lapse of
time or both, would be in default) under any contract or other agreement to use
any of the LSC Licensed Technology;

          (f) it has not previously granted and will not grant any rights or
licenses with respect to the LSC Licensed Technology in the Field of Use or in
conflict with the rights and licenses granted herein;

          (g) to the knowledge of LSC, none of the LSC Licensed Technology
infringes or conflicts with, and LSC has not received any notice of infringement
of, or conflict with, any license, patent, copyright, trademark, service mark or
other intellectual property right of any other Person and, to the knowledge of
LSC, there is no infringement or unauthorized use by any Person of any of the
LSC Licensed Technology;

          (h) the validity or enforceability of any of the LSC Licensed
Technology or the title of LSC thereto has not been questioned in any
litigation, governmental inquiry or proceeding to which LSC is a party and, to
the knowledge of LSC, no such litigation, governmental inquiry or proceeding is
threatened;

          (i) as of the Effective Date, except for the LSC Patents, the LSC
Patent Applications and the LSC Excluded Technology, LSC does not control any
patent or patent application claiming or disclosing inventions relating to or
useful in the Field of Use;

          (j) as of the Effective Date, the patents and patent applications set
forth in Appendices A and B constitute all of the LSC Patents and LSC Patent
Applications, are owned by LSC and to LSC's knowledge, are not subject to an
ownership interest or a claim of an ownership interest therein by a third party;

          (k) to LSC's knowledge as of the Effective Date, the practice and use
of the LSC Licensed Technology within the Field of Use will not infringe any
intellectual property right of a third party;

          (l) LSC has taken all reasonable actions necessary or appropriate to
preserve the confidentiality of all trade secrets and proprietary or
confidential information or material related to the LSC Licensed Technology; and

          (m) as of the Effective Date, the Additional LSC Subs are [NONE] and
there are no other Additional Licensees.

     7.2. Indemnification of LSC. Other than as provided in Section 7.3, in no
event shall LSC be liable for any use by LSO of the LSC Licensed Technology or
any loss, claim, damage or liability of any kind or nature, which may arise from
or in connection with acts by LSO under this Agreement or the use of the LSC
Licensed Technology by LSO. LSO shall indemnify, defend and hold harmless LSC,
including its directors, officers, employees, and agents, against any and all
Damages resulting from or arising out of (a) the breach of any representation or
warranty made by LSO in this Agreement, (b) any breach or violation of, or
failure to properly perform, any covenant or agreement made by LSO in this
Agreement or (c) the possession,

<PAGE>

manufacture, use, sale or other disposition of Licensed Products by LSO or its
sublicensees, whether based on breach of warranty, negligence, product liability
or otherwise, except to the extent such Damages result from a breach by LSC of
any representation, warranty, covenant or agreement of LSC or the gross
negligence or willful misconduct of LSC.

     7.3. Indemnification of LSO. LSC agrees to indemnify, defend and hold LSO
and its respective directors, officers, employees and agents harmless from and
against any and all Damages resulting from or arising out of [ * ].

     7.4. DISCLAIMER OF LIABILITY. NOTWITHSTANDING ANYTHING ELSE IN THIS
AGREEMENT OR OTHERWISE, NEITHER LSC, THE ADDITIONAL LSC SUBS NOR LSO WILL BE
LIABLE WITH RESPECT TO ANY SUBJECT MATTER OF THIS AGREEMENT UNDER ANY CONTRACT,
NEGLIGENCE, STRICT LIABILITY OR OTHER LEGAL OR EQUITABLE THEORY FOR ANY
INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LOST PROFITS.

     7.5. DISCLAIMER OF WARRANTIES. EXCEPT AS SPECIFICALLY PROVIDED IN THIS
AGREEMENT, NEITHER LSO NOR LSC MAKES ANY WARRANTIES OF ANY KIND, WHETHER EXPRESS
OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

     7.6. ESSENTIAL TERMS. THE PARTIES ACKNOWLEDGE AND AGREE THAT THE PROVISIONS
UNDER THIS AGREEMENT THAT LIMIT LIABILITY, DISCLAIM WARRANTIES, OR EXCLUDE
CONSEQUENTIAL DAMAGES OR OTHER DAMAGES OR REMEDIES ARE ESSENTIAL TERMS OF THIS
AGREEMENT THAT ARE FUNDAMENTAL TO THE PARTIES' UNDERSTANDING REGARDING
ALLOCATION OF RISK. ACCORDINGLY, SUCH PROVISIONS SHALL BE SEVERABLE AND
INDEPENDENT OF ANY OTHER PROVISIONS AND SHALL BE ENFORCED AS SUCH, REGARDLESS OF
ANY BREACH OR OTHER OCCURRENCE HEREUNDER. WITHOUT LIMITING THE GENERALITY OF THE
FOREGOING, ALL LIMITATIONS OF LIABILITY, DISCLAIMERS OF WARRANTIES, AND
EXCLUSIONS OF CONSEQUENTIAL DAMAGES OR OTHER DAMAGES OR REMEDIES SHALL REMAIN
FULLY VALID, EFFECTIVE AND ENFORCEABLE IN ACCORDANCE WITH THEIR RESPECTIVE
TERMS, EVEN UNDER CIRCUMSTANCES THAT CAUSE ANY EXCLUSIVE REMEDY UNDER THIS
AGREEMENT TO FAIL OF ITS ESSENTIAL PURPOSE.

     7.7. Licenses With Additional LSC Subs. LSC represents and warrants that
(a) the license agreement entered into, and to be entered into, by LSC and each
Additional LSC Sub (the "Additional LSC Sub License Agreements") is and shall be
in a form substantially identical to this Agreement (other than changes to the
name of each Additional LSC Sub and the applicable field of use) and (b) no
Additional Licensee (including all Additional LSC Subs) has been granted or
shall be granted any rights with respect to LSC Licensed Technology that are
more

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beneficial, taken as a whole (without regard to field of use), to such licensee
in comparison to the rights of LSO hereunder, unless LSO is granted, in writing,
identical beneficial rights (and related obligations) at the same time of such
other grant, which it may accept or reject with respect to its Field of Use or,
in the case of a nonexclusive grant, with respect to the field of use of the
grant and/or its Field of Use; provided, however, that (i) if a subsequent
Additional Licensee has not received (and is not expected to receive shortly
thereafter) at least the Threshold Amount at the time it enters into its license
agreement for the LSC Licensed Technology, then the language of Section 1.29
hereof shall be amended to provide that the Additional Licensee counts as [ * ]
in the numerator and denominator until it has received at least the Threshold
Amount, at which time there will be a recalculation of the Pro Rata Percentage
and a retroactive adjustment; (ii) Section 5.3(b) and Section 5.3(c) of any
license agreement for the LSC Licensed Technology between LSC and a subsequent
Additional Licensee shall be adjusted to reflect that Light Sciences Oncology,
Inc. has the first right to assume LSC's rights and obligations, or take an
assignment, with respect to an Abandonment and that the rights of any subsequent
Additional Licensee will be subordinate thereto; and (iii) Section 5.7 of any
license agreement for the LSC Licensed Technology between LSC and a subsequent
Additional Licensee shall be adjusted to reflect that LSO has the first right,
but not the obligation, to assume all of LSC's rights and responsibilities with
respect to the filing, prosecution, maintenance and enforcement of the LSC
Licensed Technology under Section 5 of this Agreement in the event of a change
of control of LSC as described in Section 5.7 of this Agreement.

     7.8. Identification of Additional Licensees. LSC shall promptly notify LSO
of the name and address of each Additional Licensee (including each Additional
LSC Sub) and its field of use and the scope of its rights and obligations in
comparison to this Agreement.

8.   Term and Termination of Agreement; Dissolution of LSO; Event of Default.

     8.1. Term. This Agreement will commence on the Effective Date and, unless
earlier terminated in accordance with this Section 8, will remain in full force
and effect until the last to expire of any Royalty Periods, i.e., when LSO no
longer has an obligation to pay royalties under this Agreement (the "Term").
Notwithstanding the expiration of the Term, the License shall survive, subject
to Section 8.2, as a fully paid-up, royalty-free license.

     8.2. Insolvency. In the event of (a) the voluntary or involuntary
proceedings by or against LSO are instituted in bankruptcy under any insolvency
law, or a receiver or custodian is appointed for LSO, or proceedings are
instituted by or against LSO for corporate reorganization or the dissolution or
liquidation of LSO under Title 11 of the United States Code (the "Bankruptcy
Code"), which proceedings, if involuntary, shall not have been dismissed within
[ * ] days after the date of filing, or if LSO makes an assignment for the
benefit of creditors, or substantially all of the assets of LSO are seized or
attached and not released within [ * ] days thereafter, or LSO has rejected this
Agreement (or any license grant contained herein) under Section 365(n) of the
Bankruptcy Code, or (b) the voluntary liquidation, dissolution, winding up

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<PAGE>

or cessation of business by LSO, then in such case and at such time this
Agreement shall terminate and, notwithstanding the language in Section 2
regarding the perpetual nature of the License, the License shall terminate.

     8.3. LSC Default.

          (a) Event of Default. The following events shall be defined as an "LSC
Event of Default": (i) breach of this Agreement by LSC which remains uncured (if
curable) for [ * ] days following notice of such breach by LSO, (ii) voluntary
or involuntary proceedings by or against LSC are instituted in bankruptcy under
any insolvency law, or a receiver or custodian is appointed for LSC, or
proceedings are instituted by or against LSC for corporate reorganization or the
dissolution or liquidation of LSC under the Bankruptcy Code, which proceedings,
if involuntary, shall not have been dismissed within [ * ] days after the date
of filing, or if LSC makes an assignment for the benefit of creditors, or
substantially all of the assets of LSC are seized or attached and not released
within [ * ] days thereafter, or LSC has rejected this Agreement (or any license
grant contained herein) under Section 365(n) of the Bankruptcy Code, (iii) the
voluntary liquidation, dissolution, winding up or cessation of business by LSC
or (iv) the occurrence of an event of default under the terms of any Additional
LSC Sub License Agreement or any other license agreement between LSC and any
Additional Licensee giving rise to rights upon such event of default
substantially similar to the rights of LSO under Section 8.3(b) hereof.

          (b) Patent Prosecution and Maintenance. In the event of an LSC Event
of Default and notwithstanding Section 5 hereof (i) LSC shall [ * ].

          (c) Assignment of Patent and Patent Applications. In addition, in the
event of an LSC Event of Default, LSO and any Additional Licensees shall have
the right to jointly designate a party to whom LSC shall be obligated to assign
all of its right, title and interest in each LSC Patent and LSC Patent
Application (and all files, correspondence and other records related thereto)
and such party shall take such LSC Patent or LSC Patent Application and related
material subject to whatever agreement LSO and the Additional Licensees thereof
shall agree upon.

          (d) Irrevocable License. In addition, in the event of an LSC Event of
Default, the License granted in Section 2 shall become irrevocable, fully
paid-up and non-royalty bearing.

          (e) 365(n). All rights and licenses granted under or pursuant to this
Agreement by LSC to LSO are, and shall otherwise be deemed to be, for purposes
of Section 365(n) of the Bankruptcy Code, licenses of rights to "intellectual
property" as defined under Section 101(35A) of the Bankruptcy Code. LSO, as a
licensee of such rights under this Agreement, shall retain and may fully
exercise all of its rights and elections under the Bankruptcy Code. In the event
of the commencement of a bankruptcy proceeding by or against LSC under the
Bankruptcy Code that is not dismissed within [ * ] days after it is filed, LSO
shall be entitled to a complete duplicate of (or complete access to, as
appropriate) any such intellectual property and all embodiments of such
intellectual property, and the same, if not

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already in its possession, shall be promptly delivered to LSO (i) upon any such
commencement of a bankruptcy proceeding upon written request therefor by LSO,
unless LSC elects to continue to perform all of its obligations under this
Agreement or (ii) if not delivered under (i) above, upon the rejection of this
Agreement by or on behalf of LSC, upon written request therefor by LSO.

     8.4. Voluntary Termination and Revocation. LSO shall have the right to
terminate this Agreement (including the License) or any portion of the License,
notwithstanding any language in Section 2 to the contrary, upon sixty (60) days
prior written notice to LSC. This Agreement shall terminate if LSC revokes the
License pursuant to Section 9.2(ii).

     8.5. Effect of Termination.

          (a) Accrued Rights and Obligations. Termination of this Agreement for
any reason shall not release either party hereto from any liability which, at
the time of such termination, has already accrued to the other party or which is
attributable to a period prior to such termination, nor preclude either party
from pursuing any rights and remedies it may have hereunder or at law or in
equity with respect to any breach of this Agreement. It is understood and agreed
that monetary damages may not be a sufficient remedy for any breach of this
Agreement and that the non-breaching party may be entitled to injunctive relief
as a remedy for any breach. Such remedy shall not be deemed to be the exclusive
remedy for breach of this Agreement, but shall be in addition to all other
remedies available at law or in equity.

          (b) Return of Confidential Information. Upon termination of this
Agreement pursuant to Section 8.2 or 8.4, each party shall promptly return to
the other party all Confidential Information of the other party.

          (c) Sublicenses. In the event this Agreement is terminated pursuant to
Section 8.2, any sublicensee of LSO who is not then in material breach shall
have its sublicense converted to a direct license from LSC under the terms and
conditions of this Agreement, as further limited and restricted by the terms of
the original sublicense as then in effect.

     8.6. Survival. Subject to the provisions of this Section 8, Sections 1, 2,
4, 6, 7 (other than 7.1), 8 and 11 shall survive the expiration or termination
of this Agreement for any reason.

9.   Diligence.

     9.1. Efforts. LSO agrees to use reasonable commercial efforts to develop
and commercialize Licensed Products, to develop relationships with commercial
partners with respect to the Licensed Products, and to obtain such approvals as
may be necessary to make, have made, use, sell, offer to sell or otherwise
distribute the Licensed Products in the Field of Use.

     9.2. Activities. If LSO has not, within five (5) years of the Effective
Date of this Agreement (a) initiated commercialization of a Licensed Product,
(b) entered into a relationship with a commercial partner regarding a Licensed
Product or (c) demonstrated the commercial potential of a Licensed Product
(e.g., through diligent performance of a clinical trial), then at

<PAGE>

LSC's sole discretion, LSC may (i) convert the License granted pursuant of
Section 2 of this Agreement upon written notice to LSO to a non-exclusive
license in the Field of Use or (ii) revoke the License provided in such case LSC
reimburses LSO for all amounts paid to LSC for filing, prosecution and
maintenance expenses pursuant to Section 5 prior to the date of such revocation.

10.  Disclosures by LSC.

     During the Term, LSC shall promptly disclose to LSO all documented new
inventions, discoveries and know-how owned or controlled by LSC that (i) are
related to the LSC Licensed Technology or (ii) are necessary, useful or
requested by LSO for the research, development, manufacture or commercialization
of any Licensed Product, in each case irrespective of any Field of Use
restrictions. Such disclosure to LSO shall be in writing and shall describe such
inventions, discoveries and know-how and any application to the Field of Use
known to LSC.

11.  General Provisions.

     11.1. Assignment. This Agreement shall be assignable by either party hereto
so long as such assignee agrees in writing to be bound by the terms and
conditions of this Agreement; provided that an assignment by LSC shall be
conditioned upon receipt by LSO of satisfactory evidence of the sale, assignment
or transfer to the same assignee of the LSC Licensed Technology.

     11.2. Government Approvals. LSO shall be responsible for obtaining all
necessary governmental approvals for the development, testing, production,
distribution, sale and use of Licensed Products, as applicable, in any country
where Licensed Products shall be manufactured, used, sold, or otherwise
distributed by LSO. LSC agrees to provide LSO, at LSO's expense, with any
assistance reasonably requested by LSO in obtaining such governmental approvals.

     11.3. Governing Law; Arbitration. This Agreement shall be governed by and
construed and enforced in accordance with the laws of the State of Washington,
without reference to conflicts of laws principles. Except as specifically set
forth in Section 5.4(d), prior to engaging in any formal dispute resolution with
respect to any dispute, controversy or claim arising out of or in relation to
this Agreement or the breach, termination or invalidity thereof (each, a
"Dispute"), the respective appropriate officers of the parties shall attempt for
a period not less than [ * ] days to resolve such Dispute. Any Dispute that
cannot be settled amicably by agreement of the parties pursuant to the preceding
sentence shall be finally settled by arbitration in Seattle, Washington in
accordance with the arbitration rules of the American Arbitration Association
then in force by one or more arbitrators appointed in accordance with said
rules, provided that the appointed arbitrator(s) shall have appropriate
experience in the biotechnology industry; provided, however, that arbitration
proceeding may not be instituted until the party alleging breach of this
Agreement by the other party has given the other party not less than [ * ] days
notice to remedy any alleged breach and the other party has failed to do so. The
award rendered shall be final and binding upon both parties. The judgment
rendered by the

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arbitrator(s) shall include costs of arbitration, reasonable attorneys' fees and
reasonable costs for any expert and other witnesses. Nothing in this Agreement
shall be deemed as preventing either party from seeking injunctive relief (or
any other provisional remedy) from any court having jurisdiction over the
parties and the subject matter of the Dispute as necessary to protect either
party's name, proprietary information, trade secrets, know-how or any other
proprietary rights. Judgment upon the award may be entered in any court having
jurisdiction or application may be made to such court for judicial acceptance of
the award and an order of enforcement as the case may be.

     11.4. Severability. This Agreement is intended to be severable. Should any
part or provision of this Agreement be found to be unenforceable or invalid for
any reason, the remaining parts and provisions will remain in effect; provided,
however, that in the event of an LSC bankruptcy proceeding, this Agreement must
either be assumed or rejected in its entirety in accordance with Section 365 of
the Bankruptcy Code.

     11.5. Entire Agreement. This Agreement constitutes the entire understanding
of LSC and LSO with respect to the subject matter hereof and supersedes all
prior agreements and understandings. This Agreement may be modified only with
the written agreement of both parties.

     11.6. Force Majeure. If the performance of any part of this Agreement by
either party, or of any obligation under this Agreement, is prevented,
restricted, interfered with or delayed by reason of any cause beyond the
reasonable control of the party liable to perform, unless conclusive evidence to
the contrary is provided, the party so affected shall, upon giving written
notice to the other party, be excused from such performance to the extent of
such prevention, restriction, interference or delay, provided that the affected
party shall use its reasonable best efforts to avoid or remove such causes of
nonperformance and shall continue performance with the utmost dispatch whenever
such causes are removed. When such circumstances arise, the parties shall
discuss what, if any, modification of the terms of this Agreement may be
required in order to arrive at an equitable solution.

     11.7. Waiver. No waiver of any rights shall be effective unless expressly
consented to in writing by the party to be charged and the waiver of any breach
of default shall not constitute a waiver of any other right hereunder or any
subsequent breach or default.

     11.8. Notices. All notices and other communications hereunder will be in
writing and will be deemed given if delivered personally, by fax (receipt
confirmed), or by registered or certified mail, return receipt requested and
postage prepaid or sent by express courier service (receipt verified), to the
parties at the following addresses (or at such other addresses for a party as
will be specified by the like notice; provided, that notices of a change of
address will be effective only upon receipt thereof):

<PAGE>

          If to LSC, addressed to:

               Light Sciences Corporation
               34931 SE Douglas Street, Suite 200
               Snoqualmie, WA 98065
               Attn: President
               Telephone No.: (425) 369-2800
               Telecopy No.: (425) 369-2845

               Copy to:

               ________________________________________

               ________________________________________

               ________________________________________

               Attn: __________________________________

          If to LSO, addressed to:

               Light Sciences Oncology, Inc.
               34931 SE Douglas Street, Suite 200
               Snoqualmie, WA 98065
               Attn: President
               Telephone No.: (425) 369-2800
               Telecopy No.: (425) 369-2845

               Copy to:

               ________________________________________

               ________________________________________

               ________________________________________

               Attn: __________________________________

All such notices and communications shall be deemed effective when received.

     11.9. Counterparts. This Agreement may be signed in counterparts, each of
which shall be deemed an original and all of which shall constitute one
instrument.

                            [Signature Pages Follow]

<PAGE>

THIS AGREEMENT IS ACCEPTED AND AGREED TO IN ITS ENTIRETY BY AUTHORIZED
REPRESENTATIVES OF:

"LSC"                                   "LSO"

LIGHT SCIENCES CORPORATION              LIGHT SCIENCES ONCOLOGY, INC.


/s/ Albert A. Luderer                   /s/ M.J. Winship
-------------------------------------   ----------------------------------------
Signature                               Signature

Albert A. Luderer                       M.J. Winship
Name                                    Name

CEO                                     COO
Title                                   Title

-------------------------------------   ----------------------------------------
Date                                    Date

<PAGE>

                                   APPENDIX A

                                   LSC PATENTS

                                      [ * ]

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<PAGE>

                                   APPENDIX B

                             LSC PATENT APPLICATIONS

                                      [ * ]

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<PAGE>

                                   APPENDIX C

                              LSC Trademark Status

                                  January 2005

                                      [ * ]

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<PAGE>

                                 AMENDMENT NO. 1

                                       TO

                           EXCLUSIVE LICENSE AGREEMENT

     This Amendment No.1, dated as of June 23, 2006, is made and entered into by
and between Light Sciences Oncology, Inc., a Washington corporation ("LSO"); and
Light Sciences Corporation, a Washington corporation ("LSC").

                                    RECITALS

     A. LSO and LSC previously entered into an Exclusive License Agreement,
dated as of October 5, 2005 (the "Original Agreement").

     B. LSC and Light Sciences Acquisition, LLC ("LLC") anticipate entering into
an Agreement and Plan of Merger pursuant to which LSC shall be merged into the
LLC under Washington law (the "Merger"), and the separate corporate existence of
LSC shall cease and the LLC shall change its name to Light Sciences, LLC.

     C. In anticipation of the Merger, LSO and LSC desire to amend the Original
Agreement as set forth below.

                                    AGREEMENT

     LSO and LSC therefore agree as follows:

     1. Amendments to Definitions

          (a) Section 1.19 of the Original Agreement is hereby amended to read
in its entirety as follows:

               "1.19. "LSC Improvements" shall mean any new or useful invention,
          process or improvement, patentable or unpatentable, relating to or
          arising from the LSC Patents or LSC Patent Applications, as the case
          may be, conceived or first reduced to practice or demonstrated to have
          utility by LSC or a Subsidiary during the Term."

          (b) Section 1.20 of the Original Agreement is hereby amended to read
in its entirety as follows:

               "1.20. "LSC Know-How" shall mean any invention, discovery,
          know-how, data, formulae, information, composition, process, trade
          secret, equipment and other subject matter relating to the LSC
          Licensed Technology that is (a) owned or controlled by LSC or a
          Subsidiary during the Term and (b) necessary or useful for the
          research, development, manufacture or

<PAGE>

          commercialization of any Licensed Product in the Field of Use. LSC
          Know-How does not include LSC Excluded Technology."

          (c) Section 1.22 of the Original Agreement is hereby amended to read
in its entirety as follows:

               "1.22. "LSC Patents" shall mean the patents listed in Appendix A,
          as well as foreign counterparts thereof, patents issuing from LSC
          Patent Applications, patents that are in-licensed or controlled by LSC
          or a Subsidiary during the Term, and reexaminations, reissues, patents
          of addition and extensions of the foregoing (including, without
          limitation, any LSC Improvements relating to the foregoing). LSC
          Patents do not include LSC Excluded Technology or patents that have
          been removed from the definition pursuant to Section 5.2 or 5.3(c) due
          to the action or inaction of LSO."

          (d) Section 1.23 of the Original Agreement is hereby amended to read
in its entirety as follows:

               "1.23. "LSC Patent Applications" shall mean (a) the patent
          applications listed in Appendix B and (b) all patent applications that
          cover inventions or discoveries that are made, developed, conceived,
          first reduced to practice, in-licensed or controlled by LSC or a
          Subsidiary during the Term, as well as continuations, divisionals,
          continuations-in-part, and foreign counterparts of each of the
          foregoing subsections (a) and (b) (including, without limitation, any
          LSC Improvements relating to the foregoing). LSC Patent Applications
          do not include LSC Excluded Technology or patent applications that
          have been removed from the definition pursuant to Section 5.2 or
          5.3(c) due to the action or inaction of LSO."

          (e) A new Section 1.33 is hereby added to the Original Agreement,
which shall read as follows:

               "1.33 "Subsidiary" shall mean any Person of which LSC, directly
          or indirectly, owns or controls eighty percent (80%) or more of the
          voting securities of such Person or of an interest in the assets,
          profits or earnings of such Person, whether before or after the date
          of Amendment No. 1 to this Agreement. It is recognized that a Person
          may cease being a "Subsidiary" during the Term and that the use of the
          word "Subsidiary" in Sections 1.19, 1.20, 1.22 and 1.23 is only
          applicable with respect to intellectual property that was made,
          developed, conceived, reduced to practice, in-licensed, demonstrated
          to have utility, owned or controlled, as the case may be, by the
          Person when it was a Subsidiary."

          Sections 1.33 and 1.34 of the Original Agreement shall be renumbered
as Sections 1.34 and 1.35 respectively.

     2. Acknowledgements. LSC represents that as of the date of this Amendment,
LSC has not assigned, licensed or transferred any right, title or interest,
contingent or otherwise, in or

<PAGE>

to the LSC Licensed Technology other than to LSO pursuant to the Original
Agreement. LSO and LSC acknowledge that the Merger shall not be deemed a LSC
Change of Control for purposes of Section 5.7 of the Original Agreement. LSC
shall ensure that any intellectual property that may be necessary or useful in
the Field of Use and that was made, developed, conceived, reduced to practice,
in-licensed, demonstrated to have utility, acquired or controlled by Subsidiary
during the Term shall automatically vest in or be promptly assigned to LSC.

     3. Full Force and Effect. This Amendment shall be effective as of the date
of the Original Agreement and shall continue in effect whether or not the Merger
occurs. Except as modified by this Amendment No. 1, all other terms and
provisions of the Original Agreement shall remain in full force and effect.

<PAGE>

     IN WITNESS WHEREOF, this Amendment No. 1 is executed as of the date first
set forth above.

LSO:                                    LSC:

Light Sciences Oncology, Inc.           Light Sciences Corporation


By (Signature): /s/ Robert M. Littauer  By (Signature): /s/ James C. Chen
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Name (Print):                           Name (Print):
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