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                                                                REDACTED VERSION

                                  EXHIBIT 10.12

                                       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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                              SUBLICENSE AGREEMENT

                           DATED AS OF OCTOBER 5, 2005

                                     BETWEEN

                           LIGHT SCIENCES CORPORATION

                                       AND

                          LIGHT SCIENCES ONCOLOGY, INC.

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                              SUBLICENSE AGREEMENT

     THIS SUBLICENSE 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 has exclusively licensed certain technology and intellectual
property rights relating to a photosensitizing agent known as NPe6 or ME2906
under a License and Supply Agreement dated as of April 28, 2000 by and among
Nippon Petrochemicals Co., Ltd., Meiji Seika Kaisha, Ltd, and LSC (formerly
Light Sciences Limited Partnership), as amended by Amendment No. 1 dated
__________, 2005 and as hereafter amended from time to time (the "Meiji License
Agreement");

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

     WHEREAS, concurrent with the execution of this Agreement, LSC and LSO are
entering into a separate Exclusive License Agreement under which LSO is
exclusively licensing from LSC for the Field of Use other technology and
intellectual property rights owned or controlled by LSC (the "Lessee/LSO License
Agreement");

     WHEREAS, LSC has created certain subsidiaries and may create additional
subsidiaries, in its sole and complete discretion, which have sublicensed or
will sublicense from LSC rights under the Meiji License Agreement 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 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.

     Capitalized terms in this Agreement shall have the same meaning as those
terms are defined in the Meiji License Agreement unless specifically defined
otherwise in this Agreement. As used herein, the following terms shall have the
following meaning:

     1.1 "Additional Licensees" shall mean each Additional LSC Sub and any other
Person who has obtained a sublicense to the Meiji 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 enforcement of the Meiji Patents. A Person shall not
be deemed to be an Additional Licensee with respect to a particular Meiji Patent
if the Person (including an Additional LSC Sub) does not have an exclusive
sublicense to the particular Meiji Patent or rights with respect to the
enforcement of the particular Meiji Patent that are similar to LSO's rights set
forth in Section 5.

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For example, a Person who did not sublicense a particular patent (or
subsequently had the patent removed from the definition of "Meiji Patents" that
it was sublicensing) would not be an "Additional Licensee" for purposes of the
notices and other rights and activities described in Section 5 for "Additional
Licensees" with respect to the patent.

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

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

     1.4 "Affiliate" shall have the meaning set forth in the Meiji License
Agreement; provided, however, that the Additional LSC Subs, LSC and LSO shall
not be deemed to be Affiliates of each other or be deemed to be controlled by,
controlling or under common control with each other, for purposes of this
definition in this Agreement.

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

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

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

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

     1.9 "Effective Date" shall have the meaning set forth in the first
paragraph of this Agreement.

     1.10 "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 [ * ].

     1.11 "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.

     1.12 "Infringement Parties in Interest" shall have the meaning set forth in
Section 5.3(a).

     1.13 "Licensed Products" shall mean Bulk, Compound, Product and Kit.

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

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

     1.16 "LSC/LSO License Agreement" shall have the meaning set forth in the
Recitals.

     1.17 "Meiji Know-How" shall mean the Licensed Know-How as defined in the
Meiji License Agreement.

     1.18 "Meiji Licensed Technology" shall mean the Licensed Technology as
defined in the Meiji License Agreement.

     1.19 "Meiji Patents" shall mean the Licensed Patents as defined in the
Meiji License Agreement.

     1.20 "Meiji License Agreement" shall have the meaning set forth in the
Recitals.

     1.21 "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.

     1.22 "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.

     1.23 "Sublicense" shall have the meaning sent forth in Section 2.

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

2. Sublicense of Rights Under the Meiji License Agreement.

     2.1 Sublicense. Subject to the terms of the Meiji License Agreement, LSC
hereby grants to LSO an exclusive (even as to LSC), perpetual sublicense in the
Territory, with right to assign or sublicense, to: (a) use the Meiji Licensed
Technology and all other rights of LSC under the Meiji License Agreement 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 "Sublicense"); provided,
however, the duration of the Sublicense may only be terminated if a condition in
Section 8 occurs.

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

     2.3 Meiji License Agreement. Except for the payments to be made to Licensor
by LSC pursuant to [ * ] of the Meiji License Agreement, LSO shall comply with
and perform

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in accordance with the terms of the Meiji License Agreement and be entitled to
LSC's benefits under the Meiji License Agreement in the Field of Use. Without
the consent of LSO, LSC shall not terminate, breach or otherwise allow the
termination of the Meiji License Agreement and shall not modify, amend or waive
any provision of the Meiji License Agreement. LSC shall use its best efforts to
provide LSO the benefits under the Meiji License Agreement in the Field of Use
as if LSO were a party to the Meiji License Agreement, including enforcing its
rights thereunder as directed by LSO.

     2.4 LSO's Device. Subject to and pursuant to the terms of [ * ] of the
Meiji License Agreement, if LSO develops or acquires rights to the Device for
the Oncology Field, LSO shall be responsible for notifying and discussing with
Meiji a possible mutual agreement with respect to LSO's rights to the Device for
use with the Product in Japan.

3. Consideration.

     3.1 Cash Payments. As consideration for the Sublicense granted by LSC to
LSO under Section 2, LSO shall pay (a) any milestone payments due Licensor
pursuant to [ * ] of the Meiji License Agreement as a result of achieving a
milestone event with any Product or Kit for an Oncology Indication in the
Territory that is developed by LSO or its Affiliates or sublicensees and (b) the
royalties due Licensor pursuant to [ * ] (as reduced or adjusted pursuant to
[ * ] of the Meiji License Agreement with respect to Net Sales of Products and
Kits by LSO or its Affiliates or sublicensees in the Territory for the Field of
Use. [ * ].

     3.2 Provisions Related to Royalties. [ * ] to the payment obligations of
LSO with respect to the Net Sales of Products and Kits by LSO or its Affiliates
or sublicensees in the Territory for the Field of Use.

4. Ownership of Intellectual Property; Use of Names.

     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
Sublicense shall vest in and be owned by LSO.

     4.2 Meiji Licensed Technology. Subject to the LSC/LSO License Agreement,
any and all intellectual property created, generated or developed by or on
behalf of LSC during the Term from the use of the Meiji Licensed Technology
shall vest in and be owned by LSC.

     4.3 Joint Inventions. Any intellectual property arising or resulting from
the inventive work by one or more employees of LSC and LSO (and any other
Persons) with respect to the Meiji Licensed Technology, 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
LSC/LSO License Agreement. 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.

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     4.4 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.

5. Patent Maintenance, Extension of Patent Term and Enforcement.

     5.1 Prosecution and Maintenance. LSC shall promptly notify LSO of any
communications or information it receives regarding the filing, prosecution,
issuance and maintenance of the Meiji Patents in the Territory. LSC shall
provide LSO [ * ].

     5.2 Extension of Meiji Patent Term. Upon the request of LSO and with LSO's
reasonable cooperation, LSC shall request and cause Licensor to execute and file
any appropriate application and related documents to extend the term of any
Meiji Patent and shall provide reasonable cooperation in connection therewith
pursuant to [ * ] of the Meiji License Agreement.

     5.3 Infringement of Patents by a Third Party.

          (a) Notice. In the event that any infringement of a Meiji Patent in
the Territory 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 Meiji Patent has been
sublicensed 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 [ * ] 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 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) Sublicensee Action. If LSC gives notice of its intention not to
bring such an infringement action or fails to give notice as required in Section
5.3(a), the Infringement Parties in Interest may elect to have all future
responsibility with respect to bringing such

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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 [ * ] and execute all
necessary and proper documents and take such actions as shall be appropriate in
connection with such [ * ].

          (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.

     5.4 LSO Election. Notwithstanding the foregoing, LSO shall be entitled to
assume LSC's right to enforce any particular Meiji Patent (including bringing
any infringement action and retaining any recovery therefrom) and shall bear all
costs related thereto, provided that LSO [ * ].

     5.5 Misappropriation of Trade Secret. In the event there has been a
misappropriation of a trade secret included in the Meiji Know-How and LSC would
have a right to bring an action for misappropriation of the trade secret, [ * ].

     5.6 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 enforcement
of any of the Meiji 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 5.6 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. 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

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financially to the same extent as if LSO had not assumed LSC's rights and
responsibilities pursuant to this Section 5.6). 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 enforcement of any Meiji
Licensed Technology under this Section 5.6 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 5.6 and not defined in this Agreement
shall have the meaning set forth in the Right of First Refusal and Co-Sale
Agreement.

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. The Meiji License Agreement shall be deemed to be Confidential
Information of both parties to this Agreement, except to the extent it has
become a matter of public knowledge without fault on the part of the party. 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

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          (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
(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.

     6.5 Obligations Under Meiji License Agreement. Notwithstanding the
foregoing, the parties' confidentiality and non-use obligations with respect to
"Confidential Information" (as defined in the Meiji License Agreement) received
from Licensor shall be subject to and governed solely by the terms of [ * ] of
the Meiji License Agreement.

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 sublicenses
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;

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          (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;

          (e) its rights under the Meiji License Agreement, including its rights
to the Meiji Licensed Technology, are free and clear of all Liens;

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

          (g) to the knowledge of LSC, none of the Meiji Licensed Technology
infringes or conflicts with, and LSC has not received any notice of infringement
of, or conflict with, any sublicense, patent, copyright 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 Meiji Licensed
Technology;

          (h) to the knowledge of LSC, the validity or enforceability of any of
the Meiji Licensed Technology and the title of Licensor 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 Meiji Patents and the
patents and patent applications licensed to LSO pursuant to the LSC/LSO License
Agreement, LSC does not control any patent or patent application claiming or
disclosing inventions relating to or useful in the Field of Use;

          (j) to the knowledge of LSC, the patents and patent applications set
forth in Appendice A constitute all of the Meiji Patents, are owned by Licensor
and are not subject to an ownership interest or a claim of an ownership interest
therein by a third party;

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          (k) to the knowledge of LSC, the practice and use of the Meiji
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 Meiji Licensed Technology;

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

          (n) No event or omission has occurred with respect to the Meiji
License Agreement which (by the giving of notice of the passing of time or both)
would (i) constitute a material breach or default by LSC or, to the knowledge of
LSC, Licensor, (ii) permit termination by LSC or, to the knowledge of LSC,
Licensor or (iii) result in LSC's loss of exclusivity under the Meiji License
Agreement;

          (o) LSC has delivered a true and complete copy of the Meiji License
Agreement to LSO; and

          (p) The Meiji License Agreement is in full force and effect and none
of its terms have been amended, modified or waived.

     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 Meiji 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 Meiji
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, 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 shall 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

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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 Sublicenses With Additional LSC Subs. LSC represents and warrants that
(i) the sublicense 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); (ii) no
Additional Licensee (including all Additional LSC Subs) has been granted or
shall be granted any rights with respect to Meiji Licensed Technology that are
more 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; and (iii) Section 5.6 of any sublicense
agreement for the Meiji 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 enforcement of the Meiji Licensed Technology under Section 5 of
this Agreement in the event of a change of control of LSC as described in
Section 5.6 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.

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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 in accordance with and during the term of the Meiji License Agreement
(the "Term"). [ * ].

     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 sublicense grant contained herein) under Section 365(n) of the
Bankruptcy Code, or (b) the voluntary liquidation, dissolution, winding up 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 Sublicense, the Sublicense 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
sublicense 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 sublicense 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) Meiji Patents. In the event of an LSC Event of Default and
notwithstanding Section 5 hereof (i) LSC shall immediately notify LSO and each
Additional Licensee and (ii) LSO and any Additional Licensees shall have the
right to jointly agree with respect to all future enforcement of the Meiji
Patents (with the agreement of LSO and any Additional Licensee having an
enforcement right to any particular Meiji Patent being required for any such
joint agreement with respect to the particular Meiji Patent). In the event LSO
and the Additional Licensees thereof do not jointly agree with respect to all
future enforcement of

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particular Meiji Patents, any enforcement thereof shall be in accordance with
Section 5.

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

          (d) 365(n). All rights and sublicenses 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, sublicenses of rights to
"intellectual property" as defined under Section 101(35A) of the Bankruptcy
Code. LSO, as a sublicensee 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 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. LSO shall have the right to terminate this
Agreement (including the Sublicense) or any portion of the Sublicense,
notwithstanding any language in Section 2 to the contrary, upon sixty (60) days
prior written notice to LSC. In the event the LSC/LSO License Agreement is
terminated, either party shall have the right, exercisable during the next
twelve (12) months, to terminate this Agreement (including the Sublicense),
notwithstanding any language in Section 2 to the contrary, upon thirty (30) days
prior written notice to the other party.

     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.

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          (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 sublicense 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.

     LSO shall use commercially reasonable diligence to develop, obtain
Regulatory Approval of, and commercialize a Product (and/or, in LSO's
discretion, a Product as part of a Kit) for the Field of Use pursuant to [ * ]
of the Meiji License Agreement.

10. Disclosures of Meiji Licensed Technology.

     During the Term, LSC shall promptly disclose to LSO all new Meiji Licensed
Technology (including improvements and inventions by Licensor to the Compound or
Product developed by Licensor) that has been disclosed to LSC and, upon
reasonable request, shall cause Licensor to disclose to LSC and LSO new Meiji
Licensed Technology. 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 (as defined in
the LSC/LSO License Agreement) and LSC's rights and obligations under the Meiji
License Agreement.

     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 shall 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 5.3(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

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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 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

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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):

          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

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                                   APPENDIX A

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