<PAGE>

                                                                   EXHIBIT 10.53

                                            ***TEXT OMITTED AND FILED SEPARATELY
                                                CONFIDENTIAL TREATMENT REQUESTED
                                           UNDER 17 C.F.R. SECTIONS 200.80(b)(4)
                                                                   AND 240.24B-2

                            TARGET LICENSE AGREEMENT

                                     BETWEEN

                             GEN-PROBE INCORPORATED

                                       AND

                                TOSOH CORPORATION

                         EFFECTIVE AS OF JANUARY 1, 2004

<PAGE>

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                    PAGE
<S>                                                                                 <C>
ARTICLE 1       DEFINITIONS.....................................................      1

ARTICLE 2       GRANT OF RIGHTS.................................................      5

     2.1    Grant of License Under Patent Rights................................      5

            2.1.1    RRNA Patents...............................................      5

            2.1.2    VNA Patents................................................      5

     2.2    Limitation of Rights................................................      5

            2.2.1    Restriction on License Under the rRNA Patents..............      5

            2.2.2    Sublicensing. .............................................      6

     2.3    Ownership; No Implied Rights. ......................................      6

     2.4    Patent Marking......................................................      6

ARTICLE 3       RUNNING ROYALTIES...............................................      6

     3.1    Running Royalties...................................................      6

     3.2    Accrual of Running Royalties........................................      7

     3.3    [...***...].........................................................      7

     3.4    Running Royalties Payments..........................................      8

     3.5    Withholding Taxes...................................................      8

     3.6    Royalty Reports.....................................................      8

     3.7    Books of Accounts and Records.......................................      8

     3.8    Late Payments.......................................................      9

ARTICLE 4       REPRESENTATION AND WARRANTIES, ETC..............................      9

     4.1    Legal Right.........................................................      9

     4.2    Authorization.......................................................      9

     4.3    Required Actions....................................................      9

     4.4    Disclaimer..........................................................      9

     4.5    Limitation of Liability.............................................     10

ARTICLE 5       TERM AND TERMINATION............................................     10

     5.1    Term................................................................     10

     5.2    Material Breach by Tosoh............................................     10

     5.3    Material Breach by Gen-Probe........................................     10

     5.4    Survival............................................................     10
</TABLE>

                                      -i-      *CONFIDENTIAL TREATMENT REQUESTED

<PAGE>

                                TABLE OF CONTENTS
                                   (CONTINUED)

<TABLE>
<CAPTION>
                                                                                    PAGE
<S>                                                                                 <C>
ARTICLE 6       ARBITRATION.....................................................     10

     6.1    Arbitration.........................................................     10

ARTICLE 7       INDEMNIFICATION.................................................     11

     7.1    Indemnification.....................................................     11

     7.2    Procedure...........................................................     11

ARTICLE 8       MISCELLANEOUS...................................................     11

     8.1    Assignment..........................................................     12

     8.2    Governing Law.......................................................     12

     8.3    Counterparts........................................................     12

     8.4    No Third Party Benefits.............................................     12

     8.5    Headings............................................................     12

     8.6    Binding Effect......................................................     12

     8.7    Compliance With Law.................................................     12

     8.8    Notices.............................................................     12

     8.9    Amendment and Waiver................................................     13

     8.10   Severability........................................................     13

     8.11   Attorneys' Fees.....................................................     13

     8.12   Confidentiality.....................................................     13

     8.13   Entire Agreement....................................................     13

     8.14   Press Release.......................................................     14
</TABLE>

                                      -ii-
<PAGE>

                                                                    Confidential

                            TARGET LICENSE AGREEMENT

         THIS TARGET LICENSE AGREEMENT (this "AGREEMENT"), effective as of
January 1, 2004 (the "EFFECTIVE Date"), is by and between TOSOH CORPORATION, a
corporation duly organized under the laws of Japan, having its principal place
of business at 3-8-2, Shiba, Minato-ku, Tokyo, 105- 8623, Japan ("TOSOH"), and
GEN-PROBE INCORPORATED, a Delaware corporation, having its principal place of
business at 10210 Genetic Center Drive, San Diego, California 92121-4362, U.S.A.
("GEN-PROBE").

                                    RECITALS

         A.       Gen-Probe owns certain patents and patent applications
covering compositions, kits and processes for isolating, amplifying and
determining the presence or amount of nucleic acid derived from an organism or
virus, or members of a group of organisms or viruses.

         B.       Tosoh desires to obtain from Gen-Probe a license to develop,
make, have made, use, sell or offer for sale Licensed Products (as defined
below), and practice Licensed Methods (as defined below).

         C.       Gen-Probe is willing to grant such a license on the terms and
conditions provided herein.

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

                                   ARTICLE 1

                                   DEFINITIONS

         For purposes of this Agreement, except as otherwise expressly provided
herein or unless the context herein otherwise requires, the terms defined in
this Article shall have the meanings specified below:

         1.1      "AFFILIATE" shall mean a corporation or other legal entity
that controls, is controlled by or is under common control with either Party
directly or indirectly through one or more intermediaries. For purposes of this
definition, "control" means the legal or beneficial ownership, directly or
indirectly, of more than fifty percent (50%) of the outstanding equity
securities of a corporation which are entitled to vote in the election of
directors or persons performing similar functions, or of more than fifty percent
(50%) interest in the net assets or profits of an entity which is not a
corporation; provided that such corporation or entity shall be deemed to be an
Affiliate for purposes of this Agreement only so long as such Party maintains
such ownership or control. Notwithstanding the foregoing, if, due to compliance
by either Party with the requirements imposed by a foreign investment law or
similar law, such Party is not able to own more than fifty percent (50%) of the
outstanding shares of a joint venture company established in the country of such
law, such Party shall be entitled to regard a joint venture company of which it
owns fifty percent (50%) or less of such shares to be its Affiliate as long as
such Party has the veto power to the decisions of major corporate matters of
such joint venture

                                       1.
<PAGE>

                                                                    Confidential

company, upon written prior notice to the other Party as to the name of such
joint venture and the requirements of such law, together with documentary proof
of such requirements.

         1.2      "ASIAN COUNTRIES" shall mean Japan, People's Republic of
China, Taiwan, Republic of Korea, North Korea, Mongolia, Hong Kong, Republic of
the Philippines, Socialist Republic of Vietnam, Kingdom of Cambodia, Lao
People's Democratic Republic, Kingdom of Thailand, Singapore, Federation of
Malaysia, Republic of Indonesia, Democratic Republic of East Timor, Brunei,
Union of Myanmar, Kingdom of Bhutan, Kingdom of Nepal, People's Republic of
Bangladesh, India, Sri Lanka, Republic of Maldives, Islamic Republic of
Pakistan, Republic of Turkey, Islamic Republic of Iran, Islamic State of
Afghanistan, Azerbaijan Republic, Republic of Armenia, Republic of Uzbekistan,
Republic of Turkmenistan, Republic of Tadzhikistan, Republic of Kazakhstan,
Kyrgyz Republic, and the Republic of Russia.

         1.3      "DISPUTE" shall mean any dispute, controversy or claim between
the Parties relating to, arising out of, or in any way connected to any
provision of this Agreement or any ancillary agreements hereto.

         1.4      "EFFECTIVE DATE" shall mean the date first set forth above.

         1.5      "EXCHANGE RATE" shall mean, with respect to any amount to be
converted from a foreign currency to United States dollars hereunder, the TTS
rate quoted by the Bank of Tokyo- Mitsubishi, Limited, Tokyo, Japan on the
closing of the last banking day in Tokyo of a Royalty Period.

         1.6      [...***...] shall mean [...***...] and [...***...].

         1.7      "FIELD" shall mean the field of [...***...].

         1.8      "FIRST COMMERCIAL SALE" shall mean the first sale by Tosoh or
its Affiliate of any Licensed Product or the first practice by Tosoh or its
Affiliate of any Licensed Method for consideration (and not for demonstration,
government approval, testing or promotional purposes), whichever is earlier.

         1.9      "ISSUED VALID CLAIM" shall mean any claim of the issued and
unexpired patents included within the Patent Rights that has not been held
unenforceable or invalid by any court, governmental agency, regulatory
authority, arbitral tribunal or other body of competent jurisdiction in any
unappealable or unappealed decision.

         1.10     "LICENSED METHOD" shall mean either Ribosomal Licensed Method
or VNA Licensed Method or both.

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                       2.
<PAGE>

                                                                    Confidential

         1.11     "LICENSED PRODUCT" shall mean either Ribosomal Licensed
Product or VNA Licensed Product or both.

         1.12     "NET SALES" shall mean the aggregate amount of revenue in
United States Dollars (converted as necessary for sales made in a currency other
than United States Dollars into United States Dollars at the applicable Exchange
Rate in accordance with the definition of "Exchange Rate" above) received or
receivable by Tosoh and/or its Affiliates with respect to all Licensed Products
sold or otherwise disposed of and all Licensed Methods practiced by Tosoh or its
Affiliates for consideration during a Royalty Period (for any such Licensed
Product sold or otherwise disposed of, or Licensed Method practiced for
consideration other than cash, the sales price shall be deemed to be the average
price at which identical or similar (after reasonable adjustments) Licensed
Products or Licensed Methods sold or practiced by Tosoh or its Affiliates during
the same Royalty Period in "arms-length" transactions), less only the following:

                  (a)      running royalties paid to Gen-Probe for the same
Royalty Period under the TMA License Agreement;

                  (b)      the total amount of all credits and allowances
reasonably granted by Tosoh and its Affiliates (if any) for such Licensed
Products and Licensed Methods during such Royalty Period on account of refunds,
price reductions, price discounts or rebates, whether arising out of recalls,
rejections, returns or otherwise relating to Licensed Products sold or Licensed
Method practiced prior to such Royalty Period (and for which royalties were
previously paid hereunder);

                  (c)      the total amount of all excise taxes, sales taxes,
value added taxes, consumption taxes, customs duties and other taxes or duties
(excluding income taxes or franchise taxes) imposed with respect to such
Licensed Products sold and such Licensed Method practiced;

                  (d)      the total amount of all separately itemized
transportation charges (including packing, insurance, and freight costs)
actually incurred in connection with the sales of such Licensed Products and
practice of Licensed Method; and

                  (e)      the portion of the revenues received or receivable of
the Licensed Products (to the extent previously included in the calculation of
"Net Sales" above) reasonably allocable to recovery of costs of the rented
instruments, analyzers or similar equipment pursuant to "reagent/rental"
programs or comparable sale or lease programs (including instrument
upgrade/maintenance programs).

         1.13     "PARTY" or "PARTIES" means, in the singular, Gen-Probe or
Tosoh and in the plural, Gen-Probe and Tosoh.

         1.14     "PATENT RIGHTS" shall mean the rRNA Patents and the VNA
Patents.

         1.15     "RIBOSOMAL LICENSED METHOD" shall mean any method:
[...***...].

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                       3.
<PAGE>

                                                                    Confidential

         1.16     "RIBOSOMAL LICENSED PRODUCT" shall mean any product:
[...***...].

         1.17     "ROYALTY PERIOD" shall mean a [...***...].

         1.18     "RRNA PATENTS" shall mean (i) the patents and patent
applications identified in EXHIBIT A hereto, (ii) all other United States and
foreign patents and patent applications claiming priority from the patents or
patent applications identified in EXHIBIT A hereto and (iii) all reissues,
reexaminations, renewals and extensions, continuations, continuations-in-part,
amendments and divisions of any of the foregoing patents or patent applications
set forth in (i) and (ii).

         1.19     "SEMI-ANNUAL PERIOD" shall mean, for each calendar year, a six
month period beginning on each January 1 or July 1, without regard to whether
such dates are otherwise business days.

         1.20     "TERM" shall mean the term of this Agreement set forth in
Section 5.1.

         1.21     "TERRITORY" shall mean the United States and all other
countries in the world.

         1.22     "TMA LICENSE AGREEMENT" means that that certain TMA License
Agreement between the Parties of even date herewith.

         1.23     "UNITED STATES" shall mean the United States of America, its
territories and possessions.

         1.24     "UNITED STATES DOLLAR" or "US$" shall mean the lawful currency
of the United States. All references in this Agreement to monetary amounts shall
be to United States dollars unless otherwise stated.

         1.25     "VNA LICENSED METHOD" shall mean any method: [...***...].

         1.26     "VNA LICENSED PRODUCT" shall mean any product [...***...].

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                       4.
<PAGE>

                                                                    Confidential

         1.27     "VIRAL NUCLEIC ACID PATENTS" or "VNA PATENTS" shall mean (i)
the patents and patent applications identified in EXHIBIT B hereto, (ii) all
other United States and foreign patents and patent applications claiming
priority from the patents or patent applications identified in EXHIBIT B hereto
and (iii) all reissues, reexaminations, renewals and extensions, continuations,
continuations-in-part, amendments and divisions of any of the foregoing patents
or patent applications set forth in (i) and (ii).

                                   ARTICLE 2

                                 GRANT OF RIGHTS

         2.1      GRANT OF LICENSE UNDER PATENT RIGHTS. Subject to the terms and
conditions of this Agreement, and in particular the limitation on license set
forth in Section 2.2 (Limitation on Rights) below, Gen-Probe hereby grants
Tosoh, and Tosoh hereby accepts, a non-exclusive, non-transferable,
royalty-bearing license, to the following:

                  2.1.1    RRNA PATENTS. Gen-Probe hereby grants Tosoh, and
Tosoh hereby accepts, a non-exclusive, non-transferable, royalty-bearing license
under the rRNA Patents to develop, make, have made, use, import, offer for sale,
sell, have sold or otherwise dispose of Ribosomal Licensed Products in the Field
in the Territory, and to practice Ribosomal Licensed Methods in the Field in the
Territory; provided, however, that (i) for a period of [...***...] following the
Effective Date, such license grant by Gen-Probe expressly excludes (A) making,
having made, using, importing, offering for sale, selling, having sold or
otherwise disposing of any Ribosomal Licensed Product in any country that
determines the presence or amount of ribosomal nucleic acid derived from an
Excluded Organism, and (B) practicing any Ribosomal Licensed Method in any
country that determines the presence or amount of ribosomal nucleic acid derived
from an Excluded Organism, and (ii) following the expiration of such [...***...]
period and continuing for the term of this Agreement, such license grant by
Gen-Probe expressly excludes (A) making, having made, using, importing, offering
for sale, selling, having sold or otherwise disposing of any Ribosomal Licensed
Product in the United States that determines the presence or amount of ribosomal
nucleic acid derived from an Excluded Organism, and (B) practicing any Ribosomal
Licensed Method in the United States that determines the presence or amount of
ribosomal nucleic acid derived from an Excluded Organism.

                  2.1.2    VNA PATENTS. Gen-Probe hereby grants Tosoh, and Tosoh
hereby accepts, a non-exclusive, non-transferable, royalty-bearing license under
the VNA Patents to develop, make, have made, use, import, offer for sale, sell,
have sold or otherwise dispose of VNA Licensed Products in the Field in the
Territory, and to practice VNA Licensed Methods in the Field in the Territory.

         2.2      LIMITATION OF RIGHTS.

                  2.2.1    RESTRICTION ON LICENSE UNDER THE RRNA PATENTS. The
license rights granted by Gen-Probe to Tosoh under the rRNA Patents pursuant
Section 2.1.1, specifically excludes assay products or processes for the
detection of [...***...].

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                       5.
<PAGE>

                                                                    Confidential

                  2.2.2    SUBLICENSING. Tosoh shall have the right to
sublicense to its Affiliates the licenses granted by Gen-Probe to Tosoh under
Section 2.1 above but without any right to sublicense further. Tosoh shall not
have the right to grant a sublicense to any party other than its Affiliates
under the Patent Rights without the prior written consent of Gen-Probe.

         2.3      OWNERSHIP; NO IMPLIED RIGHTS. Gen-Probe shall retain the
unrestricted right to use, and/or license for use for any purpose whatsoever the
Patent Rights inside or outside the Field, except that Gen-Probe may not
exercise such right in contravention of, or in conflict with, the express terms
and conditions hereof. Except for the licenses and rights expressly granted
hereunder, no right, title, or interest in any discovery, invention or other
technology, data or information or any patent, copyright, trademark, or other
intellectual property rights therein owned by Gen-Probe or its Affiliates shall
be granted to Tosoh under this Agreement. Gen- Probe shall not be under any
obligation to grant to Tosoh any additional licenses and rights other than those
granted hereby.

         2.4      PATENT MARKING. If reasonably requested by Gen-Probe, Tosoh
agrees to mark a container or insert therein containing a Licensed Product under
the Patent Rights manufactured by or for Tosoh or its Affiliates hereunder with
such patent notice as may be required by the laws of a country where such
Licensed Product is sold.

                                    ARTICLE 3

                                RUNNING ROYALTIES

         3.1      RUNNING ROYALTIES. In consideration of the licenses granted
under the Patent Rights, Tosoh shall pay to Gen-Probe a royalty on the total Net
Sales of all Licensed Products sold or otherwise disposed of by Tosoh and its
Affiliates for consideration and the Licensed Methods practiced by Tosoh and its
Affiliates for consideration during a Royalty Period. Tosoh shall pay to
Gen-Probe the following royalties for Licensed Products (or Licensed Methods)
covered by any Issued Valid Claim of the Patent Rights:

                           (a)      For Ribosomal Licensed Products sold or
otherwise disposed of or Ribosomal Licensed Methods practiced, in the United
States: [...***...] of Net Sales of such Ribosomal Licensed Product or Ribosomal
Licensed Method;

                           (b)      For Ribosomal Licensed Products sold or
otherwise disposed of or Ribosomal Licensed Methods practiced, in Asian
Countries: [...***...] of Net Sales of such Ribosomal Licensed Product or
Ribosomal Licensed Method; and

                           (c)      For Ribosomal Licensed Products sold or
otherwise disposed of or Ribosomal Licensed Methods practiced, in all countries
other than the United States and Asian Countries: [...***...] of Net Sales of
such Ribosomal Licensed Product or Ribosomal Licensed Method.

                           (d)      For VNA Licensed Products sold or otherwise
disposed of or VNA Licensed Methods practiced in a country in the Territory:
[...***...] of Net Sales of such VNA Licensed Product or VNA Licensed Method.

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                       6.
<PAGE>

                                                                    Confidential

         In the event that a Licensed Product or a Licensed Method uses or
practices the Issued Valid Claims of both the rRNA Patents and the VNA Patents,
the royalty rates for Ribosomal Licensed Products and Ribosomal Licensed Methods
shall apply.

         3.2      ACCRUAL OF RUNNING ROYALTIES. Running royalties shall accrue
on Licensed Products or Licensed Methods only to the extent that Tosoh or its
Affiliates make, have made, use, sell, offer to sell, import or otherwise
dispose of such Licensed Products or practice such Licensed Method for
consideration in a country in the Territory in which such act would infringe an
Issued Valid Claim in that country but for the license granted hereunder;
provided, however, that no royalty shall accrue with respect to a reasonable
number of Licensed Products sold or otherwise disposed by Tosoh for
demonstration, government approval, development, quality assurance, testing or
promotional purposes. For the avoidance of doubt:

                           (a)      Any running royalty shall not accrue with
respect to Licensed Products made, had made, used, imported, sold, offered for
sale or otherwise disposed of or Licensed Methods practiced, in a country in the
Territory in which (i) there exists no Issued Valid Claim or (ii) such act would
not infringe an Issued Valid Claim in that country;

                           (b)      If and when Licensed Products are made or
had made in a country in the Territory in which such act would infringe an
Issued Valid Claim in that country but for the license granted hereunder and
sold or otherwise disposed of for consideration in a country, whether or not
there exists an Issued Valid Claim in that country or whether or not such sales
or disposal would not infringe an Issued Valid Claim in that country, then the
Net Sales of the sales and disposal by Tosoh or its Affiliates of such Licensed
Products to or in the country in the Territory in which the Licensed Products
are sold or otherwise disposed of shall be used for the purpose of calculating
the running royalties.

                           (c)      If and when Licensed Products are made or
had made in a country in the Territory in which such act would not infringe an
Issued Valid Claim in that country and sold or otherwise disposed of for
consideration in a country in which such act would infringe an Issued Valid
Claim in that country, then the Net Sales of the sales and disposal by Tosoh or
its Affiliates of such Licensed Products in the country in the Territory in
which the Licensed Products are sold or otherwise disposed of shall be used for
the purpose of calculating the running royalties.

                           (d)      No running royalties shall accrue at the
time of the transfer, sale or disposal of Licensed Products by Tosoh to any of
its Affiliates or by any of its Affiliates to another Affiliate. In such event,
running royalties shall accrue at the time of the sale or disposal of Licensed
Products by such Affiliate to any third party.

         3.3      [...***...]

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                       7.
<PAGE>

                                                                    Confidential

[...***...]

         3.4      RUNNING ROYALTIES PAYMENTS. The running royalties accrued
under Section 3.2 above shall be paid by Tosoh on a Royalty Period basis.
Payments shall be made within [...***...] of the end of each Royalty Period. All
running royalties payable under Section 3.2 shall first be calculated in the
currency of sale and then converted into United States dollars based upon the
Exchange Rate, and shall be made in United States dollars without deduction of
exchange fees and bank commissions charged by the sending bank in Japan.
Payments shall be made by Tosoh to Gen-Probe by wire transfer to the bank
account as instructed by Gen-Probe in writing.

         3.5      WITHHOLDING TAXES. In the event that Tosoh is required to
withhold taxes imposed on any payment to Gen-Probe hereunder by virtue of
applicable law or regulations in Japan and/or in a country in which its
Affiliate sublicensed hereunder is located, then such withholding tax shall be
paid by Tosoh to the appropriate tax authorities on a timely basis by deducting
it from the payment due Gen-Probe, and Tosoh shall provide Gen-Probe with
official documentation and/or tax receipt on such withholdings supporting such
payment of taxes as may be required by Gen-Probe for its tax records. Upon
request by Gen-Probe, Tosoh and Gen-Probe shall cooperate in obtaining a reduced
tax rate under an international tax convention.

         3.6      ROYALTY REPORTS. A royalty report containing the following
information shall accompany each royalty payment:

                           (a)      The total revenues of Licensed Products sold
and Licensed Method practiced by Tosoh and its Affiliates during the applicable
Royalty Period;

                           (b)      Calculation of Net Sales for the applicable
Royalty Period;

                           (c)      Total Net Sales in United States dollars for
the applicable Royalty Period, together with the Exchange Rates used for
conversion; and,

                           (d)      Calculation of the royalty amount payable to
Gen-Probe for the applicable Royalty Period.

If no running royalties are due Gen-Probe for a Royalty Period, the royalty
report shall so state. All royalty reports shall be maintained in strict
confidence by Gen-Probe.

         3.7      BOOKS OF ACCOUNTS AND RECORDS. Tosoh shall keep, and shall
cause its Affiliates to which sublicenses have been granted under Section 2.2.2
hereof to keep, for a period of three (3) years after the close of each fiscal
year of Tosoh and such Affiliates, complete, true and accurate books of account
and other records containing all information and data which may be necessary to
ascertain and verify the amount of running royalties payable to Gen-Probe
hereunder, including, without limitation, detailed backup for the computations
of Net Sales. During the term of this Agreement and for a period of two (2)
years thereafter, Gen-Probe shall have the right (which Gen-Probe may not
exercise more than once during each fiscal year) to cause an independent public
accounting firm selected by Gen-Probe and acceptable to Tosoh to inspect, at
Gen-Probe's own cost, the books and records of Tosoh and its Affiliates to which

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                       8.
<PAGE>

                                                                    Confidential

sublicenses have been granted for the sole purpose of determining the accuracy
of the royalty report and calculation of running royalties. Such inspection
shall be made during normal business hours of Tosoh and such Affiliates and with
at least thirty (30) day prior notice. All the information disclosed to or
obtained by the independent public accounting firm shall not be disclosed to
anyone including Gen-Probe (except as required by applicable law or by any
court, governmental agency or regulatory authority) and shall be held in strict
confidence, except that the independent public accounting firm may disclose to
Gen-Probe whether any discrepancy in running royalties payment has been found
and the amount of such discrepancy.

         3.8      LATE PAYMENTS. In the event that any amount due Gen-Probe by
Tosoh hereunder is not paid when due, Tosoh shall, on Gen-Probe's demand pay to
Gen-Probe interest on overdue amount at the rate of [...***...] per annum from
the due date of such amount until the date such overdue payment is actually
received by Gen-Probe.

                                   ARTICLE 4

                       REPRESENTATION AND WARRANTIES, ETC.

         4.1      LEGAL RIGHT. Each Party represents and warrants that it has
all requisite power, authority and legal right to enter into this Agreement, and
to perform its obligations set forth herein.

         4.2      AUTHORIZATION. Each Party represents and warrants that the
execution, delivery and performance by it (a) have been duly authorized by all
necessary corporate or other actions of it, and (b) do not contravene, conflict
with or result in a breach of any permit, authorization or license, any charter
or any other organizational document, or any law, regulation, judgment, order,
agreement or legal or contractual obligations or restriction binding on or
otherwise affecting it.

         4.3      REQUIRED ACTIONS. Each Party represents and warrants that all
acts, conditions and things required to be done, fulfilled and performed by it
in order (a) to enable it to lawfully enter into or to perform its obligations
under this Agreement, (b) to ensure that its obligations under this Agreement
are legal, valid and binding and (c) to make this Agreement enforceable and
admissible in evidence, have been done, fulfilled and performed and will be
done, fulfilled and performed.

         4.4      DISCLAIMER. Except otherwise expressly represented and
warranted hereunder, the license and rights herein granted by Gen-Probe to Tosoh
are provided WITHOUT WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE OR ANY OTHER WARRANTY, EXPRESS OR IMPLIED. GEN-PROVE MAKES NO
REPRESENTATION OR WARRANTY THAT THE LICENSED PRODUCTS OR LICENSED METHOD WILL
NOT INFRINGE ANY PATENT OR PROPRIETARY RIGHT OF OTHERS. NOTHING IN THIS
AGREEMENT SHALL BE CONSTRUED AS A REPRESENTATION OR WARRANTY MADE BY GEN-PROBE
THAT ANY PATENT OR UTILITY MODEL WILL ISSUE BASED UPON ANY PENDING APPLICATION
THEREFOR OR THAT ANY PATENT OR UTILITY MODEL IS OR WILL BE VALID.

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                       9.
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                                                                    Confidential

         4.5      LIMITATION OF LIABILITY. IN NO EVENT SHALL EITHER PARTY BE
LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL
DAMAGES, LOSSES, COSTS OR EXPENSES OF ANY KIND, HOWEVER CAUSED ON ANY THEORY OF
LIABILITY AND WHETHER BASED IN CONTRACT OR TORT (INCLUDING NEGLIGENCE),
INCLUDING LOST PROFITS OR REVENUES AND LOSS OF GOODWILL, REGARDLESS OF WHETHER
SUCH PARTY KNOWS OR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES OR
LOSSES.

                                   ARTICLE 5

                              TERM AND TERMINATION

         5.1      TERM. This Agreement shall commence on the Effective Date and
shall remain in effect until the expiration of the last to expire patent in the
Patent Rights.

         5.2      MATERIAL BREACH BY TOSOH. If Tosoh violates or fails to
perform any material term or covenant of this Agreement, Gen-Probe may give
written notice of such default to Tosoh. If Tosoh fails to take appropriate
steps to cure such default within sixty (60) days of the effective date of such
notice of default, Gen-Probe shall have the right to terminate this Agreement by
issuing a written notice of termination to Tosoh without prejudice to any rights
or remedies available under this Agreement, at law or in equity. The license,
rights and benefits previously granted to Tosoh hereunder shall terminate
automatically on the effective date of such notice of termination.

         5.3      MATERIAL BREACH BY GEN-PROBE. If Gen-Probe violates or fails
to perform any material term or covenant of this Agreement, Tosoh may give
written notice of such default to Gen-Probe. If Gen-Probe fails to take
appropriate steps to cure such default within sixty (60) days of the effective
date of such notice of default, Tosoh shall have the right to (a) continue this
Agreement in full force and effect, or (b) terminate this Agreement as a whole
by issuing a written notice of termination to Gen-Probe. In all events, Tosoh
may pursue all available remedies under this Agreement, at law or equity against
Gen-Probe by reason of such breach.

         5.4      SURVIVAL. The following shall survive the expiration or
termination of this Agreement:

                           (a)      Tosoh's obligations to pay running royalties
that have accrued prior to termination; and

                           (b)      The provisions of Sections 3.7, 4.4, 4.5,
6.1, 7.1, 7.2, 8.2, 8.7, 8.8, 8.11, 8.12 and this Section 5.4.

                                   ARTICLE 6

                                   ARBITRATION

         6.1      ARBITRATION. In the event of any Dispute, the Parties shall
seek to settle their differences amicably between themselves, including entering
into non-binding mediation. Any

                                      10.
<PAGE>

unresolved Dispute shall be resolved by final and binding arbitration in
accordance with this Article. Whenever a Party shall decide to institute
arbitration proceedings, it shall give written notice to that effect to the
other Party. The Party giving such notice shall refrain from instituting the
arbitration proceedings for a period of ten (10) days following such notice to
allow the Parties to attempt to resolve the Dispute. If the Parties are still
unable to resolve the Dispute, the Party giving notice may institute the
arbitration proceedings under the rules of Arbitration of the International
Chamber of Commerce as then in effect (the "ICC RULES"). Arbitration shall be
held in The Hague, Netherlands. The arbitration shall be conducted in English
before three arbitrators, with each Party to select one arbitrator and with the
third arbitrator to be appointed in accordance with the ICC Rules. The
arbitrators shall not have the power to award punitive damages or any award of
multiple damages under this Agreement and such awards are expressly prohibited.
Any arbitration award shall be final and binding on the Parties. Judgment on the
award may be entered in any court having jurisdiction. Nothing contained in this
Article shall prevent either Party from seeking temporary restraining orders,
temporary or permanent injunctions or such other relief in any court of
competent jurisdiction.

                                   ARTICLE 7

                                 INDEMNIFICATION

         7.1      INDEMNIFICATION. Tosoh shall indemnify, defend, and hold
harmless Gen-Probe and its Affiliates and their directors, officers, employees,
and agents and their respective successors and permitted assigns against any and
all claims, suits, losses, liability, damages, or expenses (including reasonable
attorney's fees and expenses of litigation) resulting from or arising out of the
exercise by Tosoh and its Affiliates of the licenses and rights granted herein
under the Patent Rights including any manufacture, use or sale of a Licensed
Product or practice of a Licensed Method. This indemnification shall include,
but not be limited to, any product liability.

         7.2      PROCEDURE. In the event that any such claim, action or demand
is made against Gen-Probe, Gen-Probe shall promptly upon becoming aware of any
such claim, demand or suit, notify Tosoh in writing as to the nature and
particulars of the same, promptly furnish Tosoh with copies of any and all
documents (inclusive of all correspondence and pleadings other than
attorney-client communications) pertaining thereto, and provide Tosoh, at
Tosoh's expense, with reasonable cooperation for Tosoh to mitigate a loss or
damage arising from any such claim, demand or suit. Gen-Probe shall also keep
Tosoh continuously and fully informed in a timely manner as to the status of the
same and shall provide Tosoh with copies of any additional documents pertaining
thereto in a timely manner. The obligations of Tosoh under Section 7.1 shall be
contingent upon (a) Gen-Probe giving prompt written notice to Tosoh of any
indemnified claim, action or demand as provided above, (b) Gen-Probe allowing
Tosoh to control the defense and related settlement negotiations, including the
selection of one attorney or law firm to represent Gen-Probe (who may also be
the Gen-Probe's attorney or law firm), and (c) Gen- Probe fully assisting in the
defense so long as Tosoh agrees to pay Gen-Probe's out-of-pocket expenses.

                                      11.
<PAGE>

                                                                    Confidential

                                    ARTICLE 8

                                  MISCELLANEOUS

         8.1      ASSIGNMENT. Neither Party to this Agreement shall have the
right to assign, delegate or otherwise transfer any rights or obligations under
this Agreement without the prior written consent of the other Party, which shall
not be unreasonably withheld. Any such purported transfer without such prior
written consent shall be deemed void and without effect.

         8.2      GOVERNING LAW. This Agreement will be construed and governed
by the laws of the State of New York, without giving effect to conflict of law
provisions.

         8.3      COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, and all of which
together shall be deemed to be one and the same instrument.

         8.4      NO THIRD PARTY BENEFITS. Nothing in this Agreement, express or
implied, is intended to confer on any person other than the Parties and their
Affiliates or their respective successors or permitted assigns, any benefits,
rights or remedies.

         8.5      HEADINGS. All headings in this Agreement are for convenience
only and shall not affect the meaning of any provision hereof.

         8.6      BINDING EFFECT. This Agreement shall inure to the benefit of
and be binding upon the Parties and their Affiliates and their respective
successors and assigns.

         8.7      COMPLIANCE WITH LAW. Nothing contained in this Agreement shall
be construed so as to require the commission of any act contrary to law, and
wherever there is any conflict between any provision of this Agreement and any
statute, law, ordinance or treaty, the latter shall prevail, but in such event
the affected provisions of the Agreement shall be conformed and limited only to
the extent necessary to bring it within the applicable legal requirements.

         8.8      NOTICES. All notices, requests, demands and other
communications required or permitted to be given pursuant to this Agreement
shall be in writing and in English, and shall be deemed to have been duly given
upon the date of receipt if delivered by hand, recognized international
overnight courier, confirmed facsimile transmission, or registered or certified
mail, return receipt requested, postage prepaid to the following addresses or
facsimile numbers:

         If to Gen-Probe:                   If to Tosoh:

         Gen-Probe Incorporated             Tosoh Corporation
         10210 Genetic Center Drive         3-8-2 Shiba, Minato-ku
         San Diego, California 92121-4362   Tokyo 105-8623
         U.S.A.                             Japan
         Attn: Chairman                     Attn: Senior General Manager
                                            Scientific Instruments Division
                                            Facsimile:  [...***...]

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                      12.
<PAGE>

                                                                    Confidential

Either Party may change its designated address and facsimile number by notice to
the other Party in the manner provided in this Section.

         8.9      AMENDMENT AND WAIVER. This Agreement may be amended,
supplemented, or otherwise modified only by means of a written instrument signed
by both Parties. Any waiver of any rights or failure to act in a specific
instance shall relate only to such instance and shall not be construed as an
agreement to waive any rights or fail to act in any other instance, whether or
not similar.

         8.10     SEVERABILITY. In the event that any provision of this
Agreement shall, for any reason, be held to be invalid, or unenforceable in any
respect, such invalidity or unenforceability shall not affect any other
provision hereof, and the Parties shall negotiate in good faith to modify the
Agreement to preserve (to the extent possible) their original intent.

         8.11     ATTORNEYS' FEES. If either Party commences an arbitration or
other action against the other Party to enforce any of the terms hereof or
because of the material breach by such other Party of any of the terms or
covenants hereof, the prevailing Party shall be entitled, in addition to any
other relief granted, to all reasonable out-of-pocket costs and expenses
incurred by the prevailing Party in connection with such action, including,
without limitation, all reasonable attorneys' fees, and a right to such costs
and expenses shall be deemed to have accrued upon the commencement of such
action and shall be enforceable whether or not such action is prosecuted to
judgment.

         8.12     CONFIDENTIALITY. Except as required by law or a court or
administrative order, terms of this Agreement and all information disclosed
hereunder and designated as confidential shall be considered as confidential
information of the disclosing Party and the receiving Party shall use the same
care to protect such information as it uses to protect its own confidential
information of like kind. This confidentiality obligation shall not apply:

                           (a)      to information which was generally available
to the public at the time of disclosure, or information which becomes available
to the public after disclosure by the disclosing Party other than through fault
of the receiving Party; or

                           (b)      to information which has been already known
to the receiving Party prior to its receipt from the disclosing Party; or

                           (c)      to information which is obtained at any time
lawfully from a third party under circumstances permitting its disclosure to
others; or

                           (d)      to information which is developed
independently by the receiving Party other than through knowledge of the
information received from the disclosing Party.

         Notwithstanding the foregoing, promptly after the execution of this
Agreement, the Parties shall agree upon the substance of information that can be
used to describe the terms of the transaction contemplated by this Agreement so
that the Parties can disclose such information, as may be modified by mutual
written agreement from time to time, without the other party's consent.

                                      13.
<PAGE>

                                                                    Confidential

         8.13     ENTIRE AGREEMENT. This Agreement constitutes the entire
agreement between the Parties with respect to the subject matter hereof.

         8.14     PRESS RELEASE. Neither Party hereto shall issue any press
release or other public announcement relating to this Agreement without
obtaining the other Party's written approval, which will not be unreasonably
withheld.

         IN WITNESS WHEREOF, the undersigned have duly executed and delivered
this Agreement as a sealed instrument effective as of the date first above
written.

GEN-PROBE INCORPORATED

By:   /s/ Henry L. Nordhoff
    ----------------------------------------
      Henry L. Nordhoff
      Chief Executive Officer and Chairman

TOSOH CORPORATION

By:   /s/ Madoka Tashiro
    ----------------------------------------
      Madoka Tashiro
      Chief Executive Officer and Chairman

                                      14.
<PAGE>

                                                                    Confidential

                                    EXHIBIT A

                                   [...***...]

                                   [...***...]

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                      15.
<PAGE>

                                                                    Confidential

                                    EXHIBIT B

                                   [...***...]

                                   [...***...]

                                               *CONFIDENTIAL TREATMENT REQUESTED

                                      16.