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                                                                    EXHIBIT 10.3

                          REGISTRATION RIGHTS AGREEMENT

            This Registration Rights Agreement (this "Agreement") is made and
entered into as of October 12, 2004, by and among Halozyme Therapeutics, Inc., a
Nevada corporation (the "Company"), and the purchasers listed on Schedule I
hereto (the "Purchasers").

            This Agreement is being entered into pursuant to the Securities
Purchase Agreement dated as of the date hereof among the Company and the
Purchasers (the "Purchase Agreement").

            The Company and the Purchasers hereby agree as follows:

      1.    Definitions.

            Capitalized terms used and not otherwise defined herein shall have
the meanings given such terms in the Purchase Agreement. As used in this
Agreement, the following terms shall have the following meanings:

            "Affiliate" means, with respect to any Person, any other Person that
directly or indirectly controls or is controlled by or under common control with
such Person. For the purposes of this definition, "control," when used with
respect to any Person, means the possession, direct or indirect, of the power to
direct or cause the direction of the management and policies of such Person,
whether through the ownership of voting securities, by contract or otherwise;
and the terms of "affiliated," "controlling" and "controlled" have meanings
correlative to the foregoing.

            "Board" means the Company's Board of Directors.

            "Business Day" means any day except Saturday, Sunday and any day
which shall be a legal holiday or a day on which banking institutions in the
state of New York generally are authorized or required by law or other
government actions to close.

            "Closing Date" means the date of the closing of the purchase and
sale of the Shares pursuant to the Purchase Agreement.

            "Commission" means the Securities and Exchange Commission.

            "Common Stock" means the Company's Common Stock, par value $0.001
per share.

            "Effectiveness Date" means with respect to the Registration
Statement the earlier of the 90th day (or the 120th day in the event the
Registration Statement is reviewed by the Commission, including, without
limitation, any form of "modified" or "limited" review) following the Closing
Date or the date which is within five (5) Business Days of the date on which the
Commission informs the Company (i) that the Commission will not review the
Registration Statement or (ii) that the Company may request the acceleration of
the effectiveness of the Registration Statement and the Company makes such
request.

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            "Effectiveness Period" shall have the meaning set forth in Section
2.

            "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

            "Filing Date" means the 30th day following the Closing Date.

            "Holder" or "Holders" means the holder or holders, as the case may
be, from time to time of Registrable Securities.

            "Indemnified Party" shall have the meaning set forth in Section
5(c).

            "Indemnifying Party" shall have the meaning set forth in Section
5(c).

            "Losses" shall have the meaning set forth in Section 5(a).

            "Person" means an individual or a corporation, partnership, trust,
incorporated or unincorporated association, joint venture, limited liability
company, joint stock company, government (or an agency or political subdivision
thereof) or other entity of any kind.

            "Proceeding" means an action, claim, suit, investigation or
proceeding (including, without limitation, an investigation or partial
proceeding, such as a deposition), whether commenced or threatened.

            "Prospectus" means the prospectus included in the Registration
Statement (including, without limitation, a prospectus that includes any
information previously omitted from a prospectus filed as part of an effective
registration statement in reliance upon Rule 430A promulgated under the
Securities Act), as amended or supplemented by any prospectus supplement, with
respect to the terms of the offering of any portion of the Registrable
Securities covered by the Registration Statement, and all other amendments and
supplements to the Prospectus, including post-effective amendments, and all
material incorporated by reference in such Prospectus.

            "Registrable Securities" means (i) the shares of Common Stock issued
to the Purchasers pursuant to the Purchase Agreement and (ii) the shares of
Common Stock issuable upon exercise of the Warrants; provided, however, such
securities shall no longer be deemed Registrable Securities if (i) a
Registration Statement covering such shares has been declared effective by the
SEC and continues to be effective during the Effectiveness Period; or (ii) such
shares are sold in compliance with Rule 144 or may be sold pursuant to Rule
144(k).

            "Registration Statement" means the registration statements and any
additional registration statements contemplated by Section 2, including (in each
case) the Prospectus, amendments and supplements to such registration statement
or Prospectus, including pre- and post-effective amendments, all exhibits
thereto, and all material incorporated by reference in such registration
statement.

            "Rule 144" means Rule 144 promulgated by the Commission pursuant to
the Securities Act, as such Rule may be amended from time to time, or any
similar rule or regulation hereafter adopted by the Commission having
substantially the same effect as such Rule.

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            "Rule 415" means Rule 415 promulgated by the Commission pursuant to
the Securities Act, as such Rule may be amended from time to time, or any
similar rule or regulation hereafter adopted by the Commission having
substantially the same effect as such Rule.

            "Securities Act" means the Securities Act of 1933, as amended.

      2.    Resale Registration.

            On or prior to the Filing Date the Company shall prepare and file
with the Commission a Registration Statement covering the resale of the
Registrable Securities as would permit or facilitate the sale and distribution
of all the Registrable Securities in the manner reasonably requested by the
Holders. The Registration Statement shall be on Form S-3 (except if the Company
is not then eligible to register for resale the Registrable Securities on Form
S-3, in which case such registration shall be on another appropriate form in
accordance with the Securities Act and the rules promulgated thereunder). The
Company shall (i) not permit any securities other than the Registrable
Securities to be included in the Registration Statement and (ii) use
commercially reasonable efforts to cause the Registration Statement to be
declared effective under the Securities Act as promptly as possible after the
filing thereof, but in any event prior to the Effectiveness Date, and to keep
such Registration Statement continuously effective under the Securities Act
until such date as is the earlier of (x) the date when all Registrable
Securities covered by such Registration Statement have been sold; (y) the date
on which the Registrable Securities may be sold without any restriction pursuant
to Rule 144 as determined by the counsel to the Company pursuant to a written
opinion letter, addressed to the Company's transfer agent to such effect, or (z)
the second (2nd) anniversary of the Closing Date (the "Effectiveness Period").

      3.    Registration Procedures.

            In connection with the Company's registration obligations hereunder,
the Company shall:

            (a)   Prepare and file with the Commission on or prior to the Filing
Date, a Registration Statement on Form S-3 (or if the Company is not then
eligible to register for resale the Registrable Securities on Form S-3 such
registration shall be on another appropriate form in accordance with the
Securities Act and the rules and regulations promulgated thereunder) in
accordance with the method or methods of distribution thereof as specified by
the Holders (except if otherwise directed by the Holders), and use commercially
reasonable efforts to cause the Registration Statement to become effective and
remain effective as provided herein.

            (b)   Prepare and file with the Commission such amendments,
including post-effective amendments, to the Registration Statement as may be
necessary to keep the Registration Statement continuously effective as to the
applicable Registrable Securities for the Effectiveness Period and prepare and
file with the Commission such additional Registration Statements, if necessary,
in order to register for resale under the Securities Act all of the Registrable
Securities; (ii) cause the related Prospectus to be amended or supplemented by
any required Prospectus supplement, and as so supplemented or amended to be
filed pursuant to Rule 424 (or any similar provisions then in force) promulgated
under the Securities Act; (iii) respond

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promptly to any comments received from the Commission with respect to the
Registration Statement or any amendment thereto and promptly provide the Holders
true and complete copies of all correspondence from and to the Commission
relating to the Registration Statement; and (iv) comply in all material respects
with the provisions of the Securities Act and the Exchange Act with respect to
the disposition of all Registrable Securities covered by the Registration
Statement during the applicable period in accordance with the intended methods
of disposition by the Holders thereof set forth in the Registration Statement as
so amended or in such Prospectus as so supplemented.

            (c)   Promptly notify the Holders of Registrable Securities (i)(A)
when a Prospectus or any Prospectus supplement or post-effective amendment to
the Registration Statement is filed; (B) when the Commission notifies the
Company whether there will be a "review" of such Registration Statement and
whenever the Commission comments in writing on such Registration Statement and
(C) with respect to the Registration Statement or any post-effective amendment,
when the same has become effective; (ii) of any request by the Commission or any
other Federal or state governmental authority for amendments or supplements to
the Registration Statement or Prospectus or for additional information; (iii) of
the issuance by the Commission of any stop order suspending the effectiveness of
the Registration Statement covering any or all of the Registrable Securities or
the initiation of any Proceedings for that purpose; (iv) of the receipt by the
Company of any notification with respect to the suspension of the qualification
or exemption from qualification of any of the Registrable Securities for sale in
any jurisdiction, or the initiation or threatening of any Proceeding for such
purpose; and (v) of the occurrence of any event that makes any statement made in
the Registration Statement or Prospectus or any document incorporated or deemed
to be incorporated therein by reference untrue in any material respect or that
requires any revisions to the Registration Statement, Prospectus or other
documents so that, in the case of the Registration Statement or the Prospectus,
as the case may be, it will not contain any untrue statement of a material fact
or omit to state any material fact required to be stated therein or necessary to
make the statements therein, in the light of the circumstances under which they
were made, not misleading.

            (d)   Use commercially reasonable efforts to avoid the issuance of,
or, if issued, obtain the withdrawal of, (i) any order suspending the
effectiveness of the Registration Statement or (ii) any suspension of the
qualification (or exemption from qualification) of any of the Registrable
Securities for sale in any U.S. jurisdiction, at the earliest practicable
moment.

            (e)   If requested by the Holders of a majority of the Registrable
Securities, (i) promptly incorporate in a Prospectus supplement or
post-effective amendment to the Registration Statement such information as the
Company reasonably agrees should be included therein and (ii) make all required
filings of such Prospectus supplement or such post-effective amendment as soon
as practicable after the Company has received notification of the matters to be
incorporated in such Prospectus supplement or post-effective amendment.

            (f)   Furnish to each Holder, without charge and upon request, at
least one conformed copy of each Registration Statement and each amendment
thereto, including financial statements and schedules, and, to the extent
requested by such Person, all documents incorporated or deemed to be
incorporated therein by reference, and all exhibits (including those

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previously furnished or incorporated by reference) promptly after the filing of
such documents with the Commission.

            (g)   Promptly deliver to each Holder, without charge, as many
copies of the Prospectus or Prospectuses (including each form of prospectus) and
each amendment or supplement thereto as such Persons may reasonably request; and
the Company hereby consents to the use of such Prospectus and each amendment or
supplement thereto by each of the selling Holders in connection with the
offering and sale of the Registrable Securities covered by such Prospectus and
any amendment or supplement thereto.

            (h)   Prior to any public offering of Registrable Securities, use
commercially reasonable efforts to register or qualify or cooperate with the
selling Holders in connection with the registration or qualification (or
exemption from such registration or qualification) of such Registrable
Securities for offer and sale under the securities or Blue Sky laws of such
jurisdictions within the United States as any Holder reasonably requests in
writing, to keep each such registration or qualification (or exemption
therefrom) effective during the Effectiveness Period and to do any and all other
acts or things necessary or advisable to enable the disposition in such
jurisdictions of the Registrable Securities covered by a Registration Statement;
provided, however, the Company shall in no event be required to (x) qualify to
do business in any state where it is not then qualified or (y) take any action
that would subject it to tax or to the general service of process in any such
state where it is not then subject, or (z) comply with state securities or "blue
sky" laws of any state for which registration by coordination is unavailable to
the Company.

            (i)   Cooperate with the Holders to facilitate the timely
preparation and delivery of certificates representing Registrable Securities to
be sold pursuant to a Registration Statement, and to enable such Registrable
Securities to be in such denominations and registered in such names as any
Holder may request at least two (2) Business Days prior to any sale of
Registrable Securities.

            (j)   Upon the occurrence of any event contemplated by Section
3(c)(v), promptly prepare a supplement or amendment, including a post-effective
amendment, to the Registration Statement or a supplement to the related
Prospectus or any document incorporated or deemed to be incorporated therein by
reference, and file any other required document so that, as thereafter
delivered, neither the Registration Statement nor such Prospectus will contain
an untrue statement of a material fact or omit to state a material fact required
to be stated therein or necessary to make the statements therein, in the light
of the circumstances under which they were made, not misleading.

            (k)   Use commercially reasonable efforts to cause all Registrable
Securities relating to the Registration Statement to be listed on the OTC
Bulletin Board or any other securities exchange, quotation system or market, if
any, on which similar securities issued by the Company are then listed or traded
as and when required pursuant to the Purchase Agreement.

            (l)   The Company may require each selling Holder to furnish to the
Company information regarding such Holder and the distribution of such
Registrable Securities as is required by law to be disclosed in the Registration
Statement, and the Company may exclude

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from such registration the Registrable Securities of any such Holder who fails
to furnish such information within fifteen (15) days after receiving such
request.

            Each Holder covenants and agrees that (i) it will not sell any
Registrable Securities under the Registration Statement until it has received
copies of the Prospectus as then amended or supplemented as contemplated in
Section 3(g) and notice from the Company that such Registration Statement and
any post-effective amendments thereto have become effective as contemplated by
Section 3(c) and (ii) it and its officers, directors or Affiliates, if any, will
comply with the prospectus delivery requirements of the Securities Act as
applicable to them in connection with sales of Registrable Securities pursuant
to the Registration Statement.

            Each Holder agrees by its acquisition of such Registrable Securities
that, upon receipt of a notice from the Company of the occurrence of any event
of the kind described in Section 3(c)(ii), 3(c)(iii), 3(c)(iv), 3(c)(v) or 3(m),
such Holder will forthwith discontinue disposition of such Registrable
Securities under the Registration Statement until such Holder's receipt of the
copies of the supplemented Prospectus and/or amended Registration Statement
contemplated by Section 3(j), or until it is advised in writing by the Company
that the use of the applicable Prospectus may be resumed, and, in either case,
has received copies of any additional or supplemental filings that are
incorporated or deemed to be incorporated by reference in such Prospectus or
Registration Statement.

            (m)   If (i) there is material non-public information regarding the
Company which the Board reasonably determines not to be in the Company's best
interest to disclose and which the Company is not otherwise required to
disclose, or (ii) there is a significant business opportunity (including, but
not limited to, the acquisition or disposition of assets (other than in the
ordinary course of business) or any merger, consolidation, tender offer or other
similar transaction) available to the Company which the Board reasonably
determines not to be in the Company's best interest to disclose, then the
Company may postpone or suspend filing or effectiveness of a registration
statement for a period not to exceed thirty (30) consecutive days, provided that
the Company may not postpone or suspend its obligation under this Section 3(m)
for more than sixty (60) days in the aggregate during any 12 month period;
provided, however, that no such postponement or suspension shall be permitted
for consecutive thirty (30) day periods, arising out of the same set of facts,
circumstances or transactions.

            4.    Registration Expenses.

            All reasonable fees and expenses incident to the performance of or
compliance with this Agreement by the Company (excluding underwriters' discounts
and commissions), except as and to the extent specified in this Section 4, shall
be borne by the Company whether or not the Registration Statement is filed or
becomes effective and whether or not any Registrable Securities are sold
pursuant to the Registration Statement. The fees and expenses referred to in the
foregoing sentence shall include, without limitation, (i) all registration and
filing fees (including, without limitation, fees and expenses (A) with respect
to filings required to be made with the OTC Bulletin Board and each other
securities exchange or market on which Registrable Securities are required
hereunder to be listed, (B) with respect to filings required to be made with the
National Association of Securities Dealers, Inc. and the NASD Regulation, Inc.
and (C) in compliance with state securities or Blue Sky laws, (ii) printing
expenses (including, without

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limitation, expenses of printing certificates for Registrable Securities and of
printing prospectuses if the printing of prospectuses is requested by the
holders of a majority of the Registrable Securities included in the Registration
Statement), (iii) messenger, telephone and delivery expenses, (iv) fees and
disbursements of counsel for the Company, (v) Securities Act liability
insurance, if the Company so desires such insurance, and (vi) fees and expenses
of all other Persons retained by the Company in connection with the consummation
of the transactions contemplated by this Agreement, including, without
limitation, the Company's independent public accountants. In addition, the
Company shall be responsible for all of its internal expenses incurred in
connection with the consummation of the transactions contemplated by this
Agreement (including, without limitation, all salaries and expenses of its
officers and employees performing legal or accounting duties), the expense of
any annual audit, the fees and expenses incurred in connection with the listing
of the Registrable Securities on any securities exchange as required hereunder.

      5.    Indemnification.

            (a)   Indemnification by the Company. The Company shall,
notwithstanding any termination of this Agreement, indemnify and hold harmless
each Holder, its permitted assignees, officers, directors, agents, brokers
(including brokers who offer and sell Registrable Securities as principal as a
result of a pledge or any failure to perform under a margin call of Common
Stock), underwriters, investment advisors and employees, each Person who
controls any such Purchaser or permitted assignee (within the meaning of Section
15 of the Securities Act or Section 20 of the Exchange Act) and the officers,
directors, agents and employees of each such controlling Person, and the
respective successors, assigns, estate and personal representatives of each of
the foregoing, to the fullest extent permitted by applicable law, from and
against any and all claims, losses, damages, liabilities, penalties, judgments,
costs (including, without limitation, costs of investigation) and expenses
(including, without limitation, reasonable attorneys' fees and expenses)
(collectively, "Losses"), arising out of or relating to any untrue or alleged
untrue statement of a material fact contained in the Registration Statement, any
Prospectus, as supplemented or amended, if applicable, or arising out of or
relating to any omission or alleged omission of a material fact required to be
stated therein or necessary to make the statements therein (in the case of any
Prospectus or form of prospectus or supplement thereto, in the light of the
circumstances under which they were made) not misleading, except (i) to the
extent, but only to the extent, that such untrue statements or omissions are
based upon information regarding such Holder furnished in writing to the Company
by such Holder expressly for use in the Registration Statement, such Prospectus
or such form of Prospectus or in any amendment or supplement thereto, which
information was relied on by the Company or (ii) as a result of the failure of
such Holder to deliver a Prospectus, as amended or supplemented, to a purchaser
in connection with an offer or sale. The Company shall notify such Holder
promptly of the institution, threat or assertion of any Proceeding of which the
Company is aware in connection with the transactions contemplated by this
Agreement. Such indemnity shall remain in full force and effect regardless of
any investigation made by or on behalf of an Indemnified Party (as defined in
Section 5(c) hereof) and shall survive the transfer of the Registrable
Securities by the Holder.

            (b)   Indemnification by Purchasers. Each Purchaser and its
permitted assignees shall, severally and not jointly, indemnify and hold
harmless the Company, its

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directors, officers, agents and employees, each Person who controls the Company
(within the meaning of Section 15 of the Securities Act and Section 20 of the
Exchange Act), and the directors, officers, agents or employees of such
controlling Persons, and the respective successors, assigns, estate and personal
representatives of each of the foregoing, to the fullest extent permitted by
applicable law, from and against all Losses, as incurred, arising out of or
relating to any untrue or alleged untrue statement of a material fact contained
in the Registration Statement, any Prospectus, as supplemented or amended, if
applicable, or arising out of or relating to any omission or alleged omission of
a material fact required to be stated therein or necessary to make the
statements therein (in the case of any Prospectus or supplement thereto, in the
light of the circumstances under which they were made) not misleading, to the
extent, but only to the extent, that such untrue statement or omission is
contained in or omitted from any information so furnished in writing by such
Holder to the Company specifically for inclusion in the Registration Statement
or such Prospectus and that such information was reasonably relied upon by the
Company for use in the Registration Statement, such Prospectus or to the extent
that such information relates to such Holder or such Holder's proposed method of
distribution of Registrable Securities and was furnished in writing by such
Holder expressly for use in the Registration Statement, such Prospectus or such
Prospectus Supplement. Notwithstanding anything to the contrary contained
herein, in no event shall the liability of any Purchaser under this Section 5(b)
exceed the net proceeds to such Purchaser as a result of the sale of Registrable
Securities pursuant to a Registration Statement.

            (c)   Conduct of Indemnification Proceedings. If any Proceeding
shall be brought or asserted against any Person entitled to indemnity hereunder
(an "Indemnified Party"), such Indemnified Party promptly shall notify the
Person from whom indemnity is sought (the "Indemnifying Party") in writing, and
the Indemnifying Party shall assume the defense thereof, including the
employment of counsel reasonably satisfactory to the Indemnified Party and the
payment of all fees and expenses incurred in connection with defense thereof;
provided, that the failure of any Indemnified Party to give such notice shall
not relieve the Indemnifying Party of its obligations or liabilities pursuant to
this Agreement, except (and only) to the extent that it shall be finally
determined by a court of competent jurisdiction (which determination is not
subject to appeal or further review) that such failure shall have proximately
and materially adversely prejudiced the Indemnifying Party.

            An Indemnified Party shall have the right to employ separate counsel
in any such Proceeding and to participate in the defense thereof, but the fees
and expenses of such counsel shall be at the expense of such Indemnified Party
or Parties unless: (1) the Indemnifying Party has agreed in writing to pay such
fees and expenses; or (2) the Indemnifying Party shall have failed promptly to
assume the defense of such Proceeding and to employ counsel reasonably
satisfactory to such Indemnified Party in any such Proceeding; or (3) the named
parties to any such Proceeding (including any impleaded parties) include both
such Indemnified Party and the Indemnifying Party, and such Indemnified Party
shall have been advised by counsel (which shall be reasonably acceptable to the
Indemnifying Party) that a conflict of interest is likely to exist if the same
counsel were to represent such Indemnified Party and the Indemnifying Party (in
which case, the Indemnifying Party shall be responsible for reasonable fees and
expenses of no more than one counsel for the Indemnified Parties). The
Indemnifying Party shall not be liable for any settlement of any such Proceeding
effected without its written

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consent, which consent shall not be unreasonably withheld or delayed. No
Indemnifying Party shall, without the prior written consent of the Indemnified
Party, effect any settlement of any pending Proceeding in respect of which any
Indemnified Party is a party, unless such settlement includes an unconditional
release of such Indemnified Party from all liability on claims that are the
subject matter of such Proceeding.

            All fees and expenses of the Indemnified Party (including reasonable
fees and expenses to the extent incurred in connection with investigating or
preparing to defend such Proceeding in a manner not inconsistent with this
Section) shall be paid to the Indemnified Party, as incurred, within ten (10)
Business Days of written notice thereof to the Indemnifying Party (regardless of
whether it is ultimately determined that an Indemnified Party is not entitled to
indemnification hereunder; provided, that the Indemnifying Party may require
such Indemnified Party to undertake to reimburse all such fees and expenses to
the extent it is finally judicially determined that such Indemnified Party is
not entitled to indemnification hereunder).

            (d)   Contribution. If a claim for indemnification under Section
5(a) or 5(b) is unavailable to an Indemnified Party because of a failure or
refusal of a governmental authority to enforce such indemnification in
accordance with its terms (by reason of public policy or otherwise), then each
Indemnifying Party, in lieu of indemnifying such Indemnified Party, shall
contribute to the amount paid or payable by such Indemnified Party as a result
of such Losses, in such proportion as is appropriate to reflect the relative
fault of the Indemnifying Party and Indemnified Party in connection with the
actions, statements or omissions that resulted in such Losses as well as any
other relevant equitable considerations. The relative fault of such Indemnifying
Party and Indemnified Party shall be determined by reference to, among other
things, whether any action in question, including any untrue or alleged untrue
statement of a material fact or omission or alleged omission of a material fact,
has been taken or made by, or relates to information supplied by, such
Indemnifying, Party or Indemnified Party, and the parties' relative intent,
knowledge, access to information and opportunity to correct or prevent such
action, statement or omission. The amount paid or payable by a party as a result
of any Losses shall be deemed to include, subject to the limitations set forth
in Section 5(c), any reasonable attorneys' or other reasonable fees or expenses
incurred by such party in connection with any Proceeding to the extent such
party would have been indemnified for such fees or expenses if the
indemnification provided for in this Section was available to such party in
accordance with its terms.

            The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 5(d) were determined by pro rata
allocation or by any other method of allocation that does not take into account
the equitable considerations referred to in the immediately preceding paragraph.
No Person guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the Securities Act) shall be entitled to contribution from any Person
who was not guilty of such fraudulent misrepresentation.

            The indemnity and contribution agreements contained in this Section
are in addition to any liability that the Indemnifying Parties may have to the
Indemnified Parties. Notwithstanding anything to the contrary contained herein,
the Holders shall be liable under this Section 5(d) for only that amount as does
not exceed the greater of (i) the aggregate amount invested by such Purchaser
under the Purchase Agreement or (ii) the net proceeds to such Purchaser as a
result of the sale of Registrable Securities pursuant to a Registration
Statement.

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      6.    Rule 144.

            As long as any Holder owns any Registrable Securities, the Company
covenants to timely file (or obtain extensions in respect thereof and file
within the applicable grace period) all reports required to be filed by the
Company after the date hereof pursuant to Section 13(a) or 15(d) of the Exchange
Act and to promptly furnish the Holders with true and complete copies of all
such filings. As long as any Holder owns any Registrable Securities, if the
Company is not required to file reports pursuant to Section 13(a) or 15(d) of
the Exchange Act, it will prepare and furnish to the Holders and make publicly
available in accordance with Rule 144(c) promulgated under the Securities Act
annual and quarterly financial statements, together with a discussion and
analysis of such financial statements in form and substance substantially
similar to those that would otherwise be required to be included in reports
required by Section 13(a) or 15(d) of the Exchange Act, as well as any other
information required thereby, in the time period that such filings would have
been required to have been made under the Exchange Act. The Company further
covenants that it will take such further action as any Holder may reasonably
request, all to the extent required from time to time to enable such Person to
sell the Shares without registration under the Securities Act within the
limitation of the exemptions provided by Rule 144 promulgated under the
Securities Act, including providing any legal opinions relating to such sale
pursuant to Rule 144. Upon the request of any Holder, the Company shall deliver
to such Holder a written certification of a duly authorized officer as to
whether it has complied with such requirements.

      7.    Miscellaneous.

            (a)   Remedies. In the event of a breach by the Company or by a
Holder, of any of their obligations under this Agreement, each Holder or the
Company, as the case may be, in addition to being entitled to exercise all
rights granted by law and under this Agreement, including recovery of damages,
will be entitled to specific performance of its rights under this Agreement. The
Company and each Holder agree that monetary damages would not provide adequate
compensation for any losses incurred by reason of a breach by it of any of the
provisions of this Agreement and hereby further agrees that, in the event of any
action for specific performance in respect of such breach, it shall waive the
defense that a remedy at law would be adequate.

            (b)   Non-Effectiveness of Registration Statement. The Company and
the Purchasers agree that the Holders will suffer damages if the Registration
Statement is not declared effective by the Commission on or prior to the
Effectiveness Date. The Company and the Purchasers further agree that it would
not be feasible to ascertain the extent of such damages with precision.
Accordingly, if the Registration Statement is not declared effective by the
Commission on or prior to the Effectiveness Date, the Company shall pay an
amount as liquidated damages to each Holder equal to one and one half percent
(1.5%) of the initial investment amount in the Shares and Warrants held by such
Holder. In addition, the Company shall pay an amount equal to one and one half
percent (1.5%) of the initial investment amount in the Shares and Warrants held
by such Holder for each complete thirty (30) day period thereafter until the
Registration Statement is declared effective; provided however, that in no event
shall payments to any Holder under this Section 7(b) exceed twenty percent (20%)
of the initial investment amount in the Shares and Warrants held by such Holder.
Payments to be made

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pursuant to this Section 7(b) shall be due and payable immediately upon demand
at the option of the Holders in cash. The parties agree that the liquidated
damages represent a reasonable estimate on the part of the parties, as of the
date of this Agreement, of the amount of damages that may be incurred by the
Holders if the Registration Statement is not declared effective by the
Commission on or prior to the Effectiveness Date. Notwithstanding the foregoing,
all periods shall be tolled, including periods leading up to the Effectiveness
Date, for any delays caused directly or indirectly by the actions, or inactions,
of any Purchaser or Holder. The Company shall not be obligated to pay liquidated
damages and shall have no liability to any Purchaser or Holder due to such
delays.

            (c)   Entire Agreement; Amendment. This Agreement and the Purchase
Agreement contain the entire understanding and agreement of the parties with
respect to the matters covered hereby and, except as specifically set forth
herein or in the Purchase Agreement, neither the Company nor any Purchaser make
any representation, warranty, covenant or undertaking with respect to such
matters, and they supersede all prior understandings and agreements with respect
to said subject matter, all of which are merged herein. No provision of this
Agreement may be waived or amended other than by a written instrument signed by
the Company and the Holders of at least a majority of all Registrable Securities
then outstanding; provided that any waiver or amendment that adversely affects
any Purchaser without adversely affecting all Purchasers in a similar manner
must be approved in writing by such Purchaser. Any amendment or waiver effected
in accordance with this Section 7(c) shall be binding upon each Holder (and
their permitted assigns) and the Company.

            (d)   Notices. Any notice, demand, request, waiver or other
communication required or permitted to be given hereunder shall be in writing
and shall be effective (a) upon hand delivery by telecopy or facsimile at the
address or number designated below (if delivered on a Business Day during normal
business hours where such notice is to be received), or the first Business Day
following such delivery (if delivered other than on a Business Day during normal
business hours where such notice is to be received) or (b) on the second
Business Day following the date of mailing by express courier service, fully
prepaid, addressed to such address, or upon actual receipt of such mailing,
whichever shall first occur. The addresses for such communications shall be:

If to the Company:             Halozyme Therapeutics, Inc.
                               11588 Sorrento Valley Road
                               Suite 17
                               San Diego, CA 92121
                               Attention: President and Chief Executive Officer
                               Tel. No.: (858) 794-8889
                               Fax No.:  (858) 259-2539

with copies (which copies
shall not constitute notice
to the Company) to:            Gray Cary Ware & Freidenrich LLP
                               4365 Executive Drive, Suite 1100
                               San Diego, California 92121
                               Attention: Doug Rein

                                       11

<PAGE>

                               Tel. No.: (858) 677-1400
                               Fax No.:  (858) 677-1477

If to any Purchaser:           At the address of such Purchaser set forth on
                               Schedule I to this Agreement.

            Any party hereto may from time to time change its address for
notices by giving written notice of such changed address to the other party
hereto.

            (e)   Waivers. No waiver by either party of any default with respect
to any provision, condition or requirement of this Agreement shall be deemed to
be a continuing waiver in the future or a waiver of any other provision,
condition or requirement hereof, nor shall any delay or omission of any party to
exercise any right hereunder in any manner impair the exercise of any such right
accruing to it thereafter.

            (f)   Successors and Assigns. This Agreement shall be binding upon
and inure to the benefit of the parties and their successors and permitted
assigns and shall inure to the benefit of each Holder and its successors and
assigns. The Company may not assign this Agreement or any of its rights or
obligations hereunder without the prior written consent of each Holder. Each
Purchaser may assign its rights hereunder in the manner and to the Persons as
permitted herein and under the Purchase Agreement.

            (g)   Assignment of Registration Rights. The rights of each Holder
hereunder, including the right to have the Company register for resale
Registrable Securities in accordance with the terms of this Agreement, shall be
assignable by each Holder of all or a portion of the Registrable Securities if:
(i) the Holder agrees in writing with the transferee or assignee to assign such
rights, and a copy of such agreement is furnished to the Company within a
reasonable time after such assignment, (ii) the Company is, within a reasonable
time after such transfer or assignment, furnished with written notice of (a) the
name and address of such transferee or assignee, and (b) the securities with
respect to which such registration rights are being transferred or assigned,
(iii) following such transfer or assignment the further disposition of such
securities by the transferee or assignees is restricted under the Securities Act
and applicable state securities laws, (iv) at or before the time the Company
receives the written notice contemplated by clause (ii) of this Section, the
transferee or assignee agrees in writing with the Company to be bound by all of
the provisions of this Agreement, and (v) such transfer shall have been made in
accordance with the applicable requirements of the Purchase Agreement. The
rights to assignment shall apply to the Holders (and to subsequent) successors
and assigns. In the event of an assignment pursuant to this Section 7(g), the
Purchaser shall pay all incremental costs and expenses incurred by the Company
in connection with filing a Registration Statement (or an amendment to the
Registration Statement) to register the shares of Registrable Securities
assigned to any assignee or transferee of the Purchaser.

            (h)   Counterparts. This Agreement may be executed in any number of
counterparts, each of which when so executed shall be deemed to be an original
and, all of which taken together shall constitute one and the same Agreement. In
the event that any signature is delivered by facsimile transmission, such
signature shall create a valid binding obligation of the

                                       12

<PAGE>

party executing (or on whose behalf such signature is executed) the same with
the same force and effect as if such facsimile signature were the original
thereof.

            (i)   Termination. This Agreement shall terminate on the earlier of
(i) the date on which all remaining Registrable Securities may be sold without
restriction pursuant to Rule 144(k) of the Securities Act or (ii) the date when
all Registrable Securities have been sold.

            (j)   Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of New York, without regard
to principles of conflicts of law thereof.

            (k)   Cumulative Remedies. The remedies provided herein are
cumulative and not exclusive of any remedies provided by law.

            (l)   Severability. The provisions of this Agreement are severable
and, in the event that any court of competent jurisdiction shall determine that
any one or more of the provisions or part of the provisions contained in this
Agreement shall, for any reason, be held to be invalid, illegal or unenforceable
in any respect, such invalidity, illegality or unenforceability shall not affect
any other provision or part of a provision of this Agreement and this Agreement
shall be reformed and construed as if such invalid or illegal or unenforceable
provision, or part of such provision, had never been contained herein, so that
such provisions would be valid, legal and enforceable to the maximum extent
possible.

            (m)   Headings. The headings herein are for convenience only, do not
constitute a part of this Agreement and shall not be deemed to limit or affect
any of the provisions hereof.

                                       13

<PAGE>

            IN WITNESS WHEREOF, the parties hereto have caused this Registration
Rights Agreement to be duly executed by their respective authorized officers as
of the date first above written.

                                  HALOZYME THERAPEUTICS, INC.

                                  By:
                                      --------------------------------
                                  Name:    Jonathan Lim
                                  Title:   President and Chief Executive Officer

                            COMPANY SIGNATURE PAGE TO
                          REGISTRATION RIGHTS AGREEMENT

<PAGE>

                           PURCHASER:

                           If Purchaser is an individual:

                           Name:________________________________________________
                                   (exactly as name should appear on Securities)

                           Signature:___________________________________________

                           If Purchaser is an entity:

                           Name of entity:______________________________________
                                   (exactly as name should appear on Securities)

                           By:__________________________________________________
                           Name:________________________________________________
                           Title:_______________________________________________

                           PURCHASER SIGNATURE PAGE TO
                          REGISTRATION RIGHTS AGREEMENT

<PAGE>

                                   SCHEDULE I

                                   PURCHASERS