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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                                                    EXHIBIT 10.1




                             CO-PROMOTION AGREEMENT

                                     between

                                CYTYC CORPORATION

                                       and

                               DIGENE CORPORATION

                          Dated as of January 17, 2001




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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.


                             CO-PROMOTION AGREEMENT

        This Co-Promotion Agreement (the "Agreement") is made as of January 17,
2001 (the "Effective Date"), by and between CYTYC CORPORATION, a Delaware
corporation maintaining its principal business offices at 85 Swanson Road,
Boxborough, Massachusetts 01719 ("Cytyc"), and DIGENE CORPORATION, a Delaware
corporation maintaining its principal business offices at 1201 Clopper Road,
Gaithersburg, Maryland 20878 ("Digene").

                              W I T N E S S E T H:

        WHEREAS, Cytyc develops, manufactures and markets its ThinPrep(R) System
for medical diagnostic applications, including a replacement for the
conventional Pap smear called the ThinPrep(R) Pap Test(TM) (including any
successor tests thereto, referred to herein as the "ThinPrep Pap Test"), which
is significantly more effective than the conventional Pap smear as a screening
tool for cervical cancer;

        WHEREAS, Digene develops, manufactures and markets various diagnostic
tests for women's health, including Hybrid Capture(R) 2 HPV DNA Assays for the
detection of the human papillomavirus ("HPV"), a virus which causes certain
kinds of cervical cancer; and

        WHEREAS, Cytyc and Digene wish to enter into an exclusive relationship
to co-promote the HPV tests within the United States and Puerto Rico and share
in certain revenues from sales of the Digene's HPV tests, all upon the terms
specified in this Agreement.

        NOW, THEREFORE, in consideration of the mutual covenants set forth in
this Agreement and intending to be legally bound hereby, Cytyc and Digene agree
as follows:

                             ARTICLE I - DEFINITIONS

        For the purposes of this Agreement, the following words and phrases
shall have the following meanings:

        1.1     "Affiliate" means any corporation, company, partnership, joint
venture and/or firm which controls, is controlled by or is under common control
with a Party. For purposes of this Section 1.1, "control" shall mean (a) in the
case of corporate entities, direct or indirect ownership of at least fifty
percent (50%) of the stock or shares entitled to vote for the election of
directors; and (b) in the case of non-corporate entities, direct or indirect
ownership of at least fifty percent (50%) of the equity interests with the power
to direct the management and policies of such non-corporate entities.

        1.2     "Confidential Information" means any proprietary and/or
confidential information which may relate to the products, technology, trade
secrets, know-how, and/or other business or technical information of a Party,
whether disclosed prior to, on or after the Effective Date.

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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

        1.3     "Co-Promoted Solution" means the use of Digene Products using
samples taken from Cytyc's ThinPrep Pap Test vials.

        1.4     "Cytyc Product" means the ThinPrep Pap Test.

        1.5     "Digene Base Case" shall mean the estimated invoiced sales of
Digene Products in each relevant period of the Term in the Territory as set
forth on Schedule B attached hereto.

        1.6     "Digene Products" means Digene's various HPV diagnostic tests
for women's health, including Hybrid Capture(R) 2 HPV DNA Assays for the
detection of HPV, and also including, without limitation, those products with
the product numbers listed on Schedule G attached hereto, such Schedule G to be
updated from time to time by the Parties, based on changes in such product
numbers and the like.

        1.7     "Digene Product Revenues" means, with respect to each relevant
period during the Term, Digene's invoiced sales of Digene Products for such
period in the Territory, less [*************************************************
********************************************************************************
********************************************************************************
********************************************************************************
********************************************************************************
********************************************************************************
********************************************************************************
********************************************************************************
********************************************************************************
********************************************************************************
*******************************************].

        1.8     "Digene Fiscal Year" means Digene's fiscal year ending on June
30 of each calendar year.

        1.9     "Laboratory Sales Force" means, with respect to each Party, the
sales and other representatives of such Party responsible for promoting and/or
selling Products directly to hospitals, reference laboratories, independent
laboratories and public health laboratories (collectively, "Laboratories").

        1.10    "Managed Care Sales Force" means, with respect to each Party,
the sales and other representatives of such Party responsible for promoting
and/or selling Products directly to or seeking reimbursement coverage approval
from insurance companies, managed health care organizations and the like
(collectively, "Payers").

        1.11    "Party" means Cytyc or Digene and "Parties" means Cytyc and
Digene, in each case, as applicable.

        1.12    "Physician Sales Force" means, with respect to each Party, the
sales and other representatives of such Party responsible for promoting and/or
selling Products directly to physicians and their staff (collectively,
"Physicians").


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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

        1.13    "Product" or "Products" means either or both Cytyc Product
and/or Digene Products, as appropriate.

        1.14    "Sales Force(s)" means, collectively, one or more of the
Laboratory Sales Forces, Physician Sales Forces and/or Managed Care Sales
Forces, as applicable.

        1.15    "Term" shall have the meaning specified in Section 7.1 hereof.


        1.16    "Territory" means the United States and Puerto Rico.


                            ARTICLE II - CO-PROMOTION

        2.1     Co-Promotion. During the Term, subject to compliance with all
applicable laws, including, without limitation, all rules and regulations of the
United States Food and Drug Administration (the "FDA"), each of the Parties
agrees to use commercially reasonable efforts to promote the Co-Promoted
Solution as follows:

                2.1.1   Subject to the provisions of Article V hereof, Cytyc and
Digene shall work together in good faith to develop promotional messages,
methods and materials supporting the Co-Promoted Solution (the "Messages").
Other than the Promotions (as defined below), the Messages so developed by the
Parties will be the exclusive promotional messages, methods and materials
supporting the Co-Promoted Solution utilized by the respective Sales Forces of
the Parties. There will be three phases to the Messages, as follows:

                        (a)     During the first phase (the "ALTS Launch
Phase"), the Messages will highlight the use of Digene Products as a follow-up
test to ASCUS Pap tests and for patient management. A goal of the ALTS Launch
Phase is to lay the groundwork for expanded Messages supporting the use of
Digene Products as a front line screening device in conjunction with the
ThinPrep Pap Test.

                        (b)     During the second phase (the "Post PMA
Supplement Phase"), which will begin after Digene files a PMA Supplement for the
use of any of the Digene Products in conjunction with the Pap test as a primary
screening device, the Messages will be modified from time to time to reflect the
pending FDA approval of the PMA Supplement (to the extent allowed under FDA
regulations).

                        (c)     During the third phase (the "Full Launch
Phase"), which will begin upon FDA approval of the PMA Supplement, the Messages
will be modified to fully launch the Co-Promoted Solution for primary screening
of cervical cancer.

Preliminary Messages for each of the three phases are outlined on Schedule A
attached hereto. The Messages may be amended, from time to time, by mutual
written agreement of the Parties.

                2.1.2   Cytyc shall utilize its Physician Sales Force and
Managed Care Sales Force to promote the Co-Promoted Solution and to deliver the
Messages to Physicians and


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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

Payers, respectively, including, without limitation, utilizing commercially
reasonable efforts to promote the Co-Promoted Solution through at least (i)
[******] Physician primary details during the Co-Promotion Measurement Period
(as defined below) ending on June 30, 2001, (ii) [******] Physician primary
details during the Co-Promotion Measurement Period ending on June 30, 2002 and
(iii) [******] Physician primary details during the Co-Promotion Measurement
Period ending on June 30, 2003. Digene shall utilize its Laboratory Sales Force
to promote the Co-Promoted Solution and to deliver the Messages to Laboratories.
Cytyc may utilize its Laboratory Sales Force, in addition to its Physician Sales
Force and Managed Care Sales Force, to promote the Co-Promoted Solution and to
deliver the Messages to Laboratories, provided however that if Cytyc so utilizes
its respective Sales Forces, Cytyc and its Laboratory Sales Force will be
responsible to support the Co-Promoted Solution to Laboratories along with
Digene's Laboratory Sales Force and will coordinate such activities in advance
with Digene. Cytyc and Digene will meet monthly or as agreed to by both parties
to review co-promotion activities and the Messages being delivered.

                2.1.3   Cytyc's Physician Sales Force and Managed Care Sales
Force and Digene's Laboratory Sales Force will collaborate as appropriate to
coordinate Laboratory, Payer and Physician promotional efforts pursuant to
Section 2.1.2 within the overlapping Physician, Payer and Laboratory
organizations.

                2.1.4   Subject to the provisions of Article V hereof, each
Party will collaborate in good faith to assist the other Party in developing
promotional messages, methods and materials (collectively, "Promotions") that
are consistent with the Messages and the Products (as referred to in such
materials) promotion strategy appropriate for each Party to fulfill its
promotional obligations under this Agreement with respect to the Co-Promoted
Solution. In particular, but not in limitation of the foregoing, the parties
may, subject to mutual agreement, elect to co-develop Messages and Promotions
materials for Physicians, Payers, and Laboratories. No Messages or Promotions
materials that refer to a Party or its Products shall be distributed without the
prior review and written authorization of the Party referred to in such
materials. The Parties expect that Messages and Promotions may include, without
limitation, Physician-directed education programs, attendance at OB-GYN trade
shows, Physician-directed advertisements in OB-GYN trade journals and other
forms of public relations. In addition, the Parties agree to collaborate in good
faith to promote the Co-Promoted Solution directly to consumers.

        2.2     Promotional Conduct. Neither Cytyc nor Digene will make any
claims, warranties, or other statements regarding the other's Products other
than those contained in the Messages and Promotions (to the extent agreed upon
by the Parties), any such Product's current package insert or any other
statement expressly authorized in writing by Cytyc or Digene, as the case may
be. Each of Cytyc and Digene and their respective Sales Forces at all times will
act in a manner consistent with fair trade, fair competition and good business
ethics and will use commercially reasonable efforts to maintain favorable
relations with Physicians, Payers and Laboratories, as the case may be, and any
other person or party in connection with performing its obligations under this
Agreement.

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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

        2.3     Retained Responsibilities. Each Party shall be and remain solely
responsible for all sales of its respective Products and each Party shall have
and retain sole responsibility for sales support and training of its respective
Sales Forces.

                       ARTICLE III - CO-PROMOTION PAYMENTS

        3.1     Co-Promotion Payments. For each of the three "Co-Promotion
Measurement Periods" set forth in Schedule B attached hereto (each, a
"Co-Promotion Measurement Period"), Digene agrees to pay to Cytyc payments equal
to [*********************] percent ([****]%) of the amount by which Digene
Product Revenues for such Co-Promotion Measurement Period exceed the total
Digene Base Case for such Co-Promotion Measurement Period (collectively,
"Co-Promotion Payments").

        3.2     Payment Terms. Digene shall pay the Co-Promotion Payments to
Cytyc within forty-five (45) days after the end of each Co-Promotion Measurement
Period, by bank or cashier's check, or other immediately available funds in
United States dollars, at Cytyc's principal place of business, as set forth
above, or at such other places as Cytyc may, from time to time, specify to
Digene, or, if requested by Cytyc, shall be paid by wire transfer to an account
designated in advance by Cytyc. Digene shall be responsible for paying all taxes
(including any related interest or penalties, but excluding any applicable taxes
on net income owed by Cytyc based on such Co-Promotion Payments), however
designated, imposed as a result of the payment of any Co-Promotion Payments,
including, without limitation, any sales and value added taxes and any tax which
Digene is required to withhold or deduct from payments to Cytyc.

        3.3     Books and Records. Without limiting the generality of Section
3.4 hereof, Digene shall keep full, true and accurate books of account
containing all particulars as shall be pertinent for the purpose of showing any
Co-Promotion Payment or other amounts payable to Cytyc under this Agreement.
Such books of account shall be kept at Digene's principal place of business.
Such books and the supporting data shall be open, at all reasonable times and
upon reasonable notice during the Term, and for three (3) years after the
termination of this Agreement or five (5) years following the end of the fiscal
year to which they pertain, whichever is shorter, to the inspection of Cytyc and
its agents (including without limitation a certified public accounting firm
selected by Cytyc), which selection shall be subject to the approval of Digene,
which approval shall not be unreasonably withheld, for the purpose of verifying
Digene's Co-Promotion Payment reports provided to Cytyc pursuant to Section 3.4,
and compliance in other respects with related terms of this Agreement. The
certified public accounting firm performing the inspection shall execute a
confidentiality agreement reasonably acceptable to Digene and such accounting
firm which shall limit the disclosure to Cytyc of confidential information
disclosed to such accounting firm while performing such inspection solely to
such information as is reasonably necessary to determine if Digene has complied
with this Agreement, or if not, the amount and manner of any deficiency or
over-payment in reported Co-Promotion Payments for the period reviewed. In the
event that any such inspection reveals a deficiency in excess of ten percent
(10%) of the reported Co-Promotion Payment for the period covered by the
inspection, Digene shall promptly pay Cytyc (i) the deficiency, plus interest
(at the rate payable for overdue payment items pursuant to Section 3.6) and (ii)
the full costs of such inspection. Otherwise, Cytyc shall pay the full cost of
such inspection. In the event that any such inspection reveals an


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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

over-payment for the period covered by the inspection, Cytyc shall grant Digene
a credit to be applied against future Co-Promotion Payments in an amount equal
to the over-payment or, if this Agreement has been terminated before such credit
can be applied against future Co-Promotion Payments, subject to all other terms
and conditions of this Agreement, Cytyc shall pay such amount to Digene.

        3.4     Co-Promotion Payment Reports. Within thirty (30) days after the
end of the Digene fiscal quarters ending September 30, December 31 and March 31
of each year and within forty-five (45) days after the end of the Digene Fiscal
Year ending June 30 of each year, Digene shall deliver to Cytyc, at its
principal place of business specified in this Agreement or at such other address
as Cytyc shall, from time to time, specify to Digene in writing, true and
accurate reports, certified by an authorized executive officer of Digene, giving
such particulars of the business conducted by Digene during the preceding
three-month period under this Agreement as shall be pertinent to an accounting
of Digene Product Revenues for the immediately preceding three-month period.
Notwithstanding any other provision in this Agreement, Digene shall furnish
Cytyc, with additional information that Cytyc may reasonably request from time
to time, to the extent that such information is reasonably available, to
ascertain the billings, Co-Promotion Payments, and any other amounts due Cytyc
under this Agreement.

        3.5     Physician Details Reports. Within thirty (30) days after the end
of the Digene fiscal quarters ending September 30, December 31 and March 31 of
each year and within forty-five (45) days after the end of the Digene Fiscal
Year ending June 30 of each year, Cytyc shall deliver to Digene, at its
principal place of business specified in this Agreement or at such other address
as Digene shall, from time to time, specify to Cytyc in writing, true and
accurate reports, certified by an authorized executive officer of Cytyc, giving
such particulars of the promotions activities conducted by Cytyc during the
preceding three-month period under this Agreement that the Parties shall
reasonably agree to be included in such report, but which shall include the
actual number of primary and secondary physician details performed during such
period. The first such report shall be delivered within 30 days after March 31,
2001.

        3.6     Overdue Payments. Co-Promotion Payments shall, if overdue, bear
interest until payment at a per annum rate equal to [************] percent
([*****]%) [**************** **************************************], not to
exceed the maximum permitted by law, provided, however that the payment of such
interest shall not preclude Cytyc from exercising any other rights or remedies
it may have as a consequence of the lateness of any Co-Promotion Payments or
other payment due hereunder.

                             ARTICLE IV-EXCLUSIVITY

        4.1     Exclusive Relationship. During the Term, the Parties hereby
agree as follows:

                (a)     Neither Digene nor any of its Affiliates shall take any
action to promote, market or sell, within the Territory, Digene Products for use
with any liquid-based pap test product other than Cytyc's ThinPrep Pap Test, nor
shall it induce any other party to do so, nor shall it cooperate with any other
third party in such endeavor; provided, however, that notwithstanding the
foregoing, Digene may, alone and in collaboration with a third party, (i)



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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

continue to participate in promotional programs with third parties that are now
in existence and are listed on Schedule H attached hereto, (ii) market and sell
a Digene liquid-based collection medium to be used for HPV testing and cytology
or Digene Products to be used with such collection medium (it being understood
that the Parties may cooperate to evaluate such Digene collection medium for use
with the ThinPrep Pap Test) and (iii) if the FDA approves the use of TriPath
Imaging, Inc.'s AutoCyte PREP System for HPV testing using Digene Products,
publicly announce such approval and include statements and documentation
supporting such approval in Digene Product inserts and specifications, in
Product descriptions on Digene's website, as part of analyst and investor
presentations, and in such other comparable media as Digene and Cytyc shall
mutually agree in writing.

                (b)     Neither Cytyc nor any of its Affiliates shall take any
action to promote, market or sell, within the Territory, the ThinPrep Pap Test
for use with any HPV detection test other than Digene Products, nor shall it
induce any other party to do so, nor shall it cooperate with any other third
party in such endeavor.


                             ARTICLE V - TRADEMARKS

        5.1     Cytyc Trademarks. During the Term, in furtherance of the
purposes and subject to the terms and conditions of this Agreement, Cytyc hereby
grants Digene the non-exclusive, non-transferable right and license to use and
display Cytyc's trade names and trademarks set forth on Schedule C, solely in
connection with the promotion of the Co-Promoted Solution in accordance with the
terms of this Agreement and for no other purpose, which Schedule C Cytyc may, in
its sole discretion, revise at any time and from time to time (the "Cytyc
Trademarks").

        5.2     Digene Trademarks. During the Term, in furtherance of the
purposes and subject to the terms and conditions of this Agreement, Digene
hereby grants Cytyc the non-exclusive, non-transferable right and license to use
and display Digene's trade names and trademarks set forth on Schedule D, solely
in connection with the promotion of the Co-Promoted Solution in accordance with
the terms of this Agreement and for no other purpose, which Schedule D Digene
may, in its sole discretion, revise at any time and from time to time (the
"Digene Trademarks" and together with the Cytyc Trademarks, the "Trademarks").

        5.3     Trademark Guidelines. Any such use and display by a Party of the
other Party's Trademarks in accordance with the foregoing shall inure to the
benefit of such other Party and shall be subject to and in accordance with such
other Party's trademark usage guidelines regarding the use of such trademarks,
attached hereto as Schedule E (the "Cytyc Guidelines") in the case of the Cytyc
Trademarks and Schedule F (the "Digene Guidelines") in the case of the Digene
Trademarks, respectively. Cytyc may modify the Cytyc Guidelines at any time and
from time-to-time in its sole discretion and Digene may modify the Digene
Guidelines at any time and from time-to-time in its sole discretion. Neither
Party will alter or permit alteration of, or remove or modify or permit removal
or modification of, any tags, proprietary or copyright notices, labels,
trademarks, or other identifying marks placed by the other Party or its agents
on its respective Products or associated literature.


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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

        5.4     Cytyc Obligations. Cytyc acknowledges the great value of the
goodwill associated with the Digene Trademarks and agrees that the Digene
Trademarks are the sole property of Digene. Cytyc agrees that it shall not
assert any claim of ownership to the Digene Trademarks or otherwise interfere
with Digene's sole and exclusive rights to said Digene Trademarks. All goodwill
from use of the Digene Trademarks by Cytyc shall inure to the benefit of Digene,
and Cytyc shall not take any action in derogation of any of the rights of Digene
in the Digene Trademarks. To protect and preserve the goodwill associated with
the Digene Trademarks, Cytyc shall, without limitation, avoid deceptive,
misleading, or unethical practices that are or might be detrimental to the
Digene Products, Digene or the public, and will refrain from publishing or
employing any misleading or deceptive advertising. Cytyc shall not, during the
Term or after termination of this Agreement use, register or attempt to register
with any agency or in any jurisdiction any of the Digene Trademarks or any mark
confusingly similar therewith. Cytyc shall promote the Digene Products only
under the Digene Trademarks, and not under any other trademark or logo. Cytyc
agrees not to use the Digene Trademarks with respect to any products or
materials not provided by Digene, or in any way that might result in confusion
as to Digene and Cytyc or any third party being separate and distinct entities.
Cytyc shall provide to Digene access to and/or hard copies of all proposed uses
of the Digene Trademarks prior to such usage being made public, for Digene's
prior review and approval. Digene shall have the right to modify or alter the
way in which the Digene Trademarks appear, in accordance with the terms of this
Agreement and the Digene Guidelines. In connection therewith, Cytyc agrees that
it shall modify to Digene's satisfaction or cease the use of any Digene
Trademark to which use Digene, in its sole discretion, may object. If at any
time Cytyc breaches any of the terms of this Article 5, the trademark license
contained in Section 5.2 above shall automatically terminate.

        5.5     Digene Obligations. Digene acknowledges the great value of the
goodwill associated with the Cytyc Trademarks and agrees that the Cytyc
Trademarks are the sole property of Cytyc. Digene agrees that it shall not
assert any claim of ownership to the Cytyc Trademarks or otherwise interfere
with Cytyc's sole and exclusive rights to said Cytyc Trademarks. All goodwill
from use of the Cytyc Trademarks by Digene shall inure to the benefit of Cytyc,
and Digene shall not take any action in derogation of any of the rights of Cytyc
in the Cytyc Trademarks. To protect and preserve the goodwill associated with
the Cytyc Trademarks, Digene shall, without limitation, avoid deceptive,
misleading, or unethical practices that are or might be detrimental to the Cytyc
Products, Cytyc or the public, and will refrain from publishing or employing any
misleading or deceptive advertising. Digene shall not, during the Term or after
termination of this Agreement use, register or attempt to register with any
agency or in any jurisdiction any of the Cytyc Trademarks or any mark
confusingly similar therewith. Digene shall promote the Cytyc Products only
under the Cytyc Trademarks, and not under any other trademark or logo. Digene
agrees not to use the Cytyc Trademarks with respect to any products or materials
not provided by Cytyc, or in any way that might result in confusion as to Cytyc
and Digene or any third party being separate and distinct entities. Digene shall
provide to Cytyc access to and/or hard copies of all proposed uses of the Cytyc
Trademarks prior to such usage being made public, for Cytyc's prior review and
approval. Cytyc shall have the right to modify or alter the way in which the
Cytyc Trademarks appear, in accordance with the terms of this Agreement and the
Cytyc Guidelines. In connection therewith, Digene agrees that it shall modify to
Cytyc's satisfaction or cease the use of any Cytyc Trademark to which use Cytyc,
in its sole



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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.


discretion, may object. If at any time Digene breaches any of the terms of this
Article 5, the trademark license contained in Section 5.1 above shall
automatically terminate.

                 ARTICLE VI - CONFIDENTIALITY AND NON-DISCLOSURE

        6.1     Treatment of Confidential Information. Each Party hereto shall
maintain the Confidential Information of the other Party in confidence, and
shall not disclose, divulge or otherwise communicate such Confidential
Information to others, or use it for any purpose, except pursuant to, and in
order to carry out, the terms and objectives of this Agreement, and hereby
agrees to exercise every reasonable precaution to prevent and restrain the
unauthorized disclosure of such Confidential Information by any of its
directors, officers, employees, consultants, subcontractors, agents or
Affiliates. Without limiting the foregoing, (i) each Party shall assure that any
employee, consultant, subcontractor or other agent of such Party which will have
access to the other Party's Confidential Information will execute, or has
executed, a written confidentiality agreement having provisions substantially
similar to this Article VI, and (ii) each Party agrees not to make any
disclosure of the other Party's Confidential Information which will impair such
Party's ability to obtain United States or foreign patents on any patentable
invention or discovery described in such Confidential Information. The
Confidential Information of each Party includes, without limitation, information
about third parties disclosed by one Party to this Agreement to the other Party
to this Agreement.

        6.2     Release from Restrictions. The provisions of Section 6.1 shall
not apply to any Confidential Information disclosed hereunder which:

                (i)     was known or used by the receiving Party prior to its
        date of disclosure to the receiving Party, as evidenced by the prior
        written records of the receiving Party; or

                (ii)    either before or after the date of this disclosure to
        the receiving Party is lawfully disclosed to the receiving Party by an
        independent, unaffiliated third party rightfully in possession of the
        Confidential Information; or

                (iii)   either before or after the date of the disclosure to the
        receiving Party becomes published or generally known to the public
        through no fault or omission on the part of the receiving Party or its
        Affiliates and under no obligation of confidentiality; or

                (iv)    is required to be disclosed by the receiving Party to
        comply with applicable laws, judicial order or to comply with
        governmental regulations, provided that the receiving Party provides
        prior written notice of such disclosure to the other Party and takes
        reasonable and lawful actions to avoid and/or minimize the degree of
        such disclosure.

        6.3     Publicity. Neither Party shall originate any publicity, news
release or other public announcement, written or oral, relating to this
Agreement (including, without limitation, the terms hereof), or the existence of
an arrangement between the Parties, without the prior written approval of the
other Party except as otherwise required by law or regulation, including,
without limitation, the Securities Act of 1933, as amended (the "Securities
Act"), and the Securities Exchange Act of 1934, as amended (the "Exchange Act"),
and the rules and regulations of the


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REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

Securities and Exchange Commission (the "SEC") thereunder (provided, however,
that the applicable Party shall use its best efforts to obtain confidential
treatment of any Confidential Information included in any such disclosure by the
SEC in connection with such disclosure), or in response to a judicial order.

        6.4     Disclosure of Terms of Agreement. Without limiting the
generality of Section 6.3 hereof, except as may be required by law or
regulation, including, without limitation, the Securities Act and the Exchange
Act, and the rules and regulations of the SEC thereunder (provided, however,
that the Party shall use its best efforts to obtain confidential treatment of
any Confidential Information included in any such disclosure by the SEC in
connection with such disclosure), or in response to a judicial order, neither
Party shall disclose the terms of this Agreement without the prior written
consent of the other Party.

        6.5     Survival of Confidentiality Obligations. The foregoing
confidentiality obligations of the Parties shall remain binding on both Parties
after termination of this Agreement for a period of five (5) years. The parties
acknowledge that any breach of this Article VI will constitute irreparable harm,
and that the non-breaching Party shall be entitled to specific performance or
injunctive relief to enforce this Article VI in addition to whatever remedies
such Party may otherwise be entitled to at law or in equity.

                       ARTICLE VII - TERM AND TERMINATION

        7.1     Term. Unless earlier terminated pursuant to the terms of this
Agreement, this Agreement shall be effective upon the Effective Date and shall
continue until June 30, 2002 (the "Initial Term"). The Initial Term shall
automatically renew, unless earlier terminated pursuant to the terms of this
Agreement, for one (1) successive one (1) year period ending June 30, 2003,
subject to earlier termination (i) pursuant to this Article VII or (ii) if
either Party no later than thirty (30) days prior to the expiration of the
Initial Term notifies the other Party of its intent not to renew the Initial
Term (the Initial Term, as so renewed (if applicable) is sometimes referred to
herein as the "Term").

        7.2     Mutual Termination. This Agreement may be terminated at any time
by a written agreement signed by both Parties.


        7.3     Early Termination Events.

                (a)     If at any time during the Term (i) all or substantially
all of the assets of a Party are acquired, (ii) all or substantially all of the
capital stock of a Party is acquired, or (iii) a Party is acquired pursuant to a
merger or similar transaction or series of related transactions in which such
Party is not the surviving entity or in which the stockholders of such Party
immediately prior to such merger or similar transaction or series of related
transactions do not continue to hold at least a majority of the shares of
capital stock of such Party immediately after giving effect to such merger or
transaction or series of related transactions (each, a "Change of Control"),
then, in any such case, either Party may terminate this Agreement at any time
within sixty (60) days after the closing of such Change of Control. The acquired
Party in such Change


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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

of Control shall notify the other Party of any such Change of Control no later
than thirty (30) days after the closing of such Change of Control.

                (b)     Upon any material breach or default of this Agreement by
either Party, the Party not in default or breach (the "Non-Breaching Party") may
terminate this Agreement upon forty-five (45) days written notice to the Party
in default or breach (the "Breaching Party"), with such termination to become
effective upon expiration of said forty-five (45) day period, unless within said
forty-five (45) day period the Breaching Party shall have cured such breach or
default. Without limiting the generality of the foregoing, for purposes of this
Agreement, (i) any failure by Digene at any time to pay Co-Promotion Payments or
other amounts owed under this Agreement , (ii) any breach by a Party of the
exclusivity provisions set forth in Section 4.1 and (iii) any failure by either
Party to perform its co-promotion obligations under Article II, shall each be
deemed a material breach or default of this Agreement.

        7.4     Arbitration. The Parties agree that any claim or controversy
arising pursuant to this Agreement, or the rights or obligations of the Parties
hereunder shall be resolved solely by application of the procedures set forth in
this Section 7.4. These procedures, however, may be modified by written
agreement of the Parties with respect to any particular dispute. If the Parties
are unable to resolve such dispute within thirty (30) days, either Party may
demand arbitration by sending written notice to the other Party. Such
arbitration shall be administered by the American Arbitration Association
("AAA") in accordance with its Commercial Arbitration Rules. The arbitration
proceedings shall be conducted before one arbitrator in Washington, D.C. or any
other place selected by mutual agreement of the Parties. The arbitrator shall
apply the governing law set forth in Section 12.2 hereof. If the Parties are
unable to agree upon a single arbitrator within sixty (60) days after
arbitration is demanded, three (3) arbitrators shall be used, one selected by
each Party with ten (10) days after the conclusion of the sixty (60) day period
and a third selected by the first two within ten (10) days thereafter. The
arbitrator or arbitrators shall be accredited by the AAA and shall be
individuals with knowledge of and experience with the pharmaceutical industry.

        7.5     Consequences of Termination.

                (a)     Upon the expiration or termination of this Agreement:

                        (i)     Digene will pay Cytyc all due and outstanding
Co-Promotion Payments, as well as Co-Promotion Payments not yet due but relating
to Digene Product Revenues made prior to termination, the due date of which will
automatically be accelerated to the date of expiration or termination of this
Agreement, with payment to be made within 30 days of termination.

                        (ii)    Digene will deliver to Cytyc or its designee any
Cytyc Product within Digene's possession or control and Cytyc will deliver to
Digene or its designee any Digene Product within Cytyc's possession or control.


                                       11
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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                        (iii)   Each Party shall destroy or return, at the other
Party's option, all of the Confidential Information, and any copies thereof, of
the other Party within such Party's possession or control.

                (b)     The provisions of Articles I, III (except Section 3.1
which shall not survive), VI, VIII, IX, X, XI and XII, and Sections 5.4, 5.5,
7.4 and this Section 7.5 will survive the expiration or termination of this
Agreement.

                (c)     Termination or expiration of this Agreement shall not
relieve either Party of any then-accrued payment obligation under this
Agreement. Any and all payments, offsets or credits by either Party to the other
accrued hereunder as of the date of termination shall remain due and payable in
accordance with the terms hereof.

                (d)     Any termination or expiration of this Agreement shall
not serve to eliminate any liability arising out of conduct prior to the actual
date of termination or expiration, and either Party may, following such
termination or expiration, pursue such remedies as may be available with respect
to such liabilities. In addition, notwithstanding the termination or expiration
of this Agreement, any provisions of this Agreement specifically providing for
survival shall continue in full force and effect.

                  ARTICLE VIII - REPRESENTATIONS AND WARRANTIES

        8.1     Authorization. Each Party represents and warrants to the other
that it has the legal right, authority and power to enter into this Agreement,
to extend the rights granted or to be granted to the other in this Agreement,
and to fully perform its obligations hereunder, and that it has not made and
will not make any commitments to others in conflict with or in derogation of
such rights or this Agreement. Each Party further represents to the other that,
as of the Effective Date, and to its actual knowledge, it is not aware of any
legal obstacles, including, without limitation, patent rights of others, which
could reasonably be expected to prevent it from carrying out its obligations
under this Agreement.

        8.2     Disclaimer. EXCEPT AS SPECIFICALLY SET FORTH IN THIS AGREEMENT
AND TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, EACH PARTY HEREBY AGREES
THAT THE FOREGOING REPRESENTATIONS AND WARRANTIES CONSTITUTE SUCH PARTY'S SOLE
AND EXCLUSIVE REPRESENTATIONS AND WARRANTIES UNDER THIS AGREEMENT. EACH PARTY,
WITH RESPECT TO ITS OWN PRODUCTS, MAKES NO, AND DISCLAIMS ANY, WARRANTY OF
FITNESS FOR A PARTICULAR PURPOSE OR MERCHANTABILITY AND ANY WARRANTY AGAINST
INTERFERENCE WITH QUIET ENJOYMENT OR AGAINST INFRINGEMENT. NO ORAL, OR WRITTEN
INFORMATION OR ADVICE GIVEN BY SUCH PARTY SHALL CREATE A WARRANTY OR IN ANY WAY
INCREASE THE SCOPE OF THE AFOREMENTIONED REPRESENTATIONS AND WARRANTIES. EXCEPT
FOR THE WARRANTIES SET FORTH ABOVE, EACH PARTY EXPRESSLY DISCLAIMS ANY AND ALL
WARRANTIES, WHETHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION, ALL
EXPRESS WARRANTIES, IF ANY, MADE BY SUCH PARTY. THE FOREGOING EXCLUSIONS AND
DISCLAIMERS ARE AN ESSENTIAL PART OF THIS AGREEMENT.


                                       12


<PAGE>   14
THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                          ARTICLE IX - INDEMNIFICATION

        9.1     Indemnification. Each Party (the "Indemnifying Party") will
defend, indemnify and hold the other Party (the "Indemnified Party") harmless
from and against any damages and liabilities awarded against the Indemnified
Party and any costs and expenses, (including, without limitation, reasonable
attorney's fees) reasonably incurred by the Indemnified Party with respect to
any third party claim, suit, action or proceeding brought against the
Indemnified Party to the extent that it is based upon a claim (i) that the
Indemnifying Party's Product(s) infringe any copyright, trade secret, trademark
or patent, (ii) of wrongful death, bodily injury or physical destruction of
tangible property to the extent resulting from any acts or omissions of the
Indemnifying Party in the performance of its duties hereunder or resulting from
the production, manufacture, sale, use, lease, consumption or promotion of the
Indemnifying Party's Products or (iii) of misrepresentation, misstatement and/or
false or misleading statement by the Indemnifying Party related to the
Co-Promoted Solution and/or the Indemnified Party's Products, unless made in
reliance on statements and information provided by the Indemnified Party. The
foregoing obligation of the Indemnifying Party does not apply, and the
Indemnifying Party shall have no liability to the Indemnified Party under this
Section 9.1, for any claim arising out of the modification of a Product or
Products by anyone other than the Indemnifying Party or a party acting with
express authority on the Indemnifying Party's behalf, to the extent that the
claim would have been avoided absent such modification. The Indemnifying Party's
obligations hereunder are contingent on the following conditions:

                (a)     the Indemnified Party must notify the Indemnifying Party
in writing promptly (but in no event later than thirty (30) days) after the
Indemnified Party becomes aware of a claim or the possibility thereof; provided,
however, that failure to give prompt notice shall not relieve the Indemnifying
Party of any liability hereunder (except to the extent the Indemnifying Party
has suffered actual material prejudice by such failure); and

                (b)     the Indemnified Party must grant the Indemnifying Party
the sole control of the settlement, compromise, negotiation, and defense of any
such action, provided, however, that the Indemnifying Party may not compromise
or settle any action in a manner which admits fault or negligence on the part of
the Indemnified Party or includes injunctive relief without the prior written
consent of the Indemnified Party, and provided further that the Indemnified
Party shall be entitled to participate in such action at its own expense; and

                (c)     the Indemnified Party must provide the Indemnifying
Party with all information related to the action that is reasonably requested by
the Indemnifying Party.

        9.2     Settlements. The Indemnifying Party shall not be liable
hereunder for any settlement made by the Indemnified Party without the
Indemnifying Party's advance written approval or for any award from any action
in which the Indemnifying Party was not granted control of the defense.

        9.3     Cooperation. The Parties agree to cooperate in good faith in the
defense of any legal action or suit that causes one Party to invoke an indemnity
hereunder.


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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                       ARTICLE X - LIMITATION OF LIABILITY

        10.1    EXCEPT FOR BREACHES OF ARTICLE V (TRADEMARKS) AND ARTICLE VI
(CONFIDENTIALITY), AND FOR LIABILITY UNDER ARTICLE IX (INDEMNIFICATION), NEITHER
PARTY, NOR ANY OF ITS DIRECTORS, OFFICERS, EMPLOYEES OR AFFILIATES, SHALL BE
LIABLE FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, INCLUDING ECONOMIC
DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, REGARDLESS OF WHETHER SUCH PARTY
SHALL BE ADVISED, SHALL HAVE OTHER REASON TO KNOW, OR IN FACT SHALL KNOW OF THE
POSSIBILITY OF THE FOREGOING.


                         ARTICLE XI - PAYMENTS, NOTICES
                            AND OTHER COMMUNICATIONS

        11.1    Addresses. Any and all payments, notices or other communications
pursuant to this Agreement shall be in writing and shall be delivered (i) by
express overnight courier service (it being understood that payments may be wire
transferred to the other Party's bank account specified by such Party with a
copy of a notice of wire transfer sent as set forth in this Article XI) or (ii)
by facsimile transmission (with confirming copy to follow by express overnight
courier service):

                (a)     if to Cytyc, at 85 Swanson Road, Boxborough,
Massachusetts 01719, Attention: President, or at such other address or addresses
as may have been furnished in writing by Cytyc to Digene, with a copy to Testa,
Hurwitz & Thibeault, LLP, 125 High Street, Boston, Massachusetts 01220,
Attention: Jonathan M. Moulton, Esq.; or

                (b)     if to Digene, at Digene Corporation, 1201 Clopper Road,
Gaithersburg, Maryland 20878, Attention: President, Charles Fleischman, or at
such other address or addresses as may have been furnished in writing by Digene
to Cytyc.

        11.2    Deemed Delivery. Notices provided in accordance with this
Article IX shall be deemed delivered upon receipt of the notice by the Party
being sent the notice.

        11.3    United Stated Currency. All references in this Agreement to
dollars or amounts shall be payable in currency of the United States of America.

                     ARTICLE XII - MISCELLANEOUS PROVISIONS

*       12.1    Non-Solicitation. During the Term and for a period of
[*************] after the termination of this Agreement for any reason, neither
Party will directly or indirectly solicit the employment of any employee of the
other Party without such other Party's prior written consent, provided, however,
that either Party may, without the prior written consent of the other Party,
engage in general recruiting not specifically directed to any of the other
Party's employees, including, without limitation, placing "help-wanted" type
advertisements in newspapers and


                                       14
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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

trade journals and on radio programs and Internet-based recruiting services,
participating in job fairs and similar events open to the public, and the like.

        12.2    Governing Law. This Agreement shall be construed, governed,
interpreted and applied in accordance with the internal laws of the Commonwealth
of Massachusetts, U.S.A. without reference to its conflicts of law provisions.

        12.3    Entire Agreement; Modification. The parties hereto acknowledge
that this Agreement and all Exhibits and Schedules attached hereto set forth the
entire agreement and understanding of the Parties hereto as to the subject
matter hereof and supersede all prior understandings and writings related
thereto, and shall not be subject to any change or modification except by the
execution of a written instrument subscribed to by the Parties hereto.

        12.4    No Waiver. The failure of either party to assert a right
hereunder or to insist upon compliance with any term or condition of this
Agreement shall not constitute a waiver of that right or excuse a similar
subsequent failure to perform any such term or condition by the other party.

        12.5    Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument.

        12.6    Independent Contractors. The Parties hereto are independent
contractors and nothing contained in this Agreement shall be deemed to create
the relationship of partners, joint venturers, or of principal and agent,
franchiser and franchisee, or of any association or relationship between the
Parties other than as expressly provided in this Agreement. Digene acknowledges
that it does not have, and Digene shall not make representations to any third
party, either directly or indirectly, indicating that Digene has any authority
to act for or on behalf of Cytyc or to obligate Cytyc in any way whatsoever.
Cytyc acknowledges that it does not have, and it shall not make any
representations to any third party, either directly or indirectly, indicating
that it has any authority to act for or on behalf of Digene or to obligate
Digene in any way whatsoever.

        12.7    Severability. If any provision of this Agreement is or becomes,
at any time or for any reason, unenforceable or invalid, no other provision of
this Agreement shall be affected thereby, and the remaining provisions of this
Agreement shall be construed and reformed and shall continue with the same
effect as if such unenforceable or invalid provision shall not have been
inserted in this Agreement.

        12.8    Assignment. Neither this Agreement nor any of the rights or
obligations hereunder may be assigned by either Party without the prior written
consent of the other Party.

        12.9    Costs of Collection. In the event of any default in payment by
Digene under Article III hereof, or any other breach of this Agreement by either
party, the non-breaching Party shall be entitled to collection and prompt
reimbursement from the breaching Party for all costs (including attorneys' fees
and other expenses), claims and damages paid or incurred by such non-


                                       15
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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

breaching Party in enforcing this Agreement. Otherwise, each Party shall bear
its own expenses with respect to the execution and performance of this
Agreement.

        12.10   Language. The official language of this Agreement is English.
Documents or notices not originally written in English shall have no effect
under this Agreement until they have been translated into English and the
English translation shall then be the controlling form of the document or
notice.

        12.11   Successors and Assigns. Subject to Section 12.8 hereof, this
Agreement shall be binding upon and inure to the benefit of the Parties hereto
and their successors and permitted assigns.


            [THE REMAINDER OF THIS PAGE IS LEFT BLANK INTENTIONALLY]


                                       16

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THIS EXHIBIT HAS BEEN REDACTED AND IS THE SUBJECT OF A CONFIDENTIAL TREATMENT
REQUEST. REDACTED MATERIAL IS MARKED WITH "*" AND BRACKETS AND HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

        IN WITNESS WHEREOF, the parties hereto have duly executed this
Co-Promotion Agreement under seal as of the day and year set forth above.


                            CYTYC CORPORATION



                            By:         /s/ Patrick Sullivan
                               -------------------------------------------------
                            Name (please print):   Patrick Sullivan
                                                --------------------------------
                            Title (please print):  Chief Executive Officer
                                                 -------------------------------


                            DIGENE CORPORATION


                            By:         /s/ Evan Jones
                               -------------------------------------------------
                            Name (please print):   Evan Jones
                                                --------------------------------
                            Title (please print):  Chief Executive Officer
                                                 -------------------------------



                                       17