Exhibit 10.2

FORM OF

REGISTRATION RIGHTS AGREEMENT

THIS REGISTRATION RIGHTS AGREEMENT (this “Agreement”) is made and entered into
as of this         day of July, 2009 by and among Arrowhead Research
Corporation, a Delaware corporation (the “Company”) and the purchasers of the
Company’s Units (as defined below) listed on Exhibit A hereto, as may be amended
from time to time (the “Investors”).

RECITALS

WHEREAS, the Investors are purchasing units (the “Units”), each consisting of
one (1) share of the Company’s common stock, par value $0.001 per share (the
“Common Stock” and such shares of Common Stock under the Units, the “Shares”)
and one (1) warrant (the “Warrants”) exercisable for shares of Common Stock (the
“Warrant Shares”) or, in certain circumstances, a fractional share of the
Company’s Series A Preferred Stock, pursuant to a Subscription Agreement by and
between the Company and each Investor dated as of the date hereof (collectively,
the “Purchase Agreements”);

WHEREAS, in connection with the consummation of the transactions under the
Purchase Agreements, the Company and the Investors have agreed to the provisions
as set forth below.

NOW, THEREFORE, in consideration of these premises and intending to be legally
bound, the parties hereto agree as follows:

1. Certain Definitions. As used in this Agreement, the following terms shall
have the following respective meanings:

“Affiliate” means, with respect to any specified Person, a Person that directly,
or indirectly through one or more intermediaries, controls, or is controlled by,
or is under common control with, the specified Person, where “control”
(including the terms “controlling,” “controlled by” and “under common control
with”) means the possession, directly or indirectly, 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; provided,
however, that when used with respect to the Company, “Affiliate” shall not
include any Investor or Affiliate thereof.

“Closing Date” means the date of the closing of the purchase and sale of Units
under the Purchase Agreements.

“Commission” means the Securities and Exchange Commission or any other federal
agency at the time administering the Securities Act.

“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the
rules and regulations promulgated thereunder, or any similar federal rule or
statute and the rules and regulations of the Commission thereunder, all as the
same shall be in effect at the time.

“Registrable Securities” means any (i) Shares purchased by the Investors
pursuant to the Purchase Agreements, (ii) Warrant Shares issued or issuable upon
exercise of those certain Warrants issued pursuant to the Purchase Agreements,
and (iii) Common Stock issued or issuable in respect of the foregoing upon any
stock split, stock dividend, recapitalization or

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similar event; provided, however, that such securities shall only be treated as
Registrable Securities if and so long as they have not been sold pursuant to a
registration or in accordance with Rule 144.

The terms “register,” “registered” and “registration” refer to a registration
effected by preparing and filing a Registration Statement in compliance with the
Securities Act, and the declaration or ordering of the effectiveness of such
Registration Statement.

“Registration Expenses” shall mean all expenses, except as otherwise stated
below, incurred by the Company in complying with Section 2(a) and 2(c) hereof,
including without limitation, all registration, qualification and filing fees,
printing expenses, escrow fees, fees and disbursements of counsel for the
Company, blue sky fees and expenses, the expense of any special audits incident
to or required by any such registration (but excluding the compensation of
regular employees of the Company which shall be paid in any event by the Company
and excluding any underwriters discounts or commissions which may be
applicable). Registration Expenses shall also include the reasonable fees and
disbursements for one special counsel to the selling Investors holding
Registrable Securities reasonably acceptable to the Company, but shall not
include any other fees or expenses of the Investors.

“Registration Statements” means any one or more registration statements of the
Company filed under the Securities Act that covers the resale of any of the
Registrable Securities pursuant to the provisions of this Agreement (including
without limitation the Initial Registration Statement, the Warrant Registration
Statement, the New Registration Statement and any Remainder Registration
Statements), amendments and supplements to such Registration Statements,
including post-effective amendments, all exhibits and all material incorporated
by reference or deemed to be incorporated by reference in such Registration
Statements.

“Rule 144” and “Rule 145” shall mean Rules 144 and 145, respectively,
promulgated under the Securities Act, as such rules may be amended from time to
time, or any similar federal rules thereunder, all as the same shall be in
effect at the time.

“Securities Act” shall mean the Securities Act of 1933, as amended, and the
rules and regulations promulgated thereunder, or any similar federal rule or
statute and the rules and regulations of the Commission thereunder, all as the
same shall be in effect at the time.

2. Registration Rights.

(a) Company Registration of Shares and Warrant Shares. Subject to the receipt of
necessary information from the Investors after prompt request from the Company
to the Investor to provide such information, the Company shall: (i) use best
efforts to cause a Registration Statement on Form S-3 (or other appropriate
form) covering the resale of all of the Shares and, at the discretion of the
Company, the Warrant Shares, not already covered by an existing and effective
Registration Statement for an offering to be made on a continuous basis pursuant
to Rule 415 or, if Rule 415 is not available for offers and sales of the
Registrable Securities, by such other means of distribution of Registrable
Securities as the Investors may reasonably specify (the “Initial Registration
Statement”), to be filed with the Commission within 30 days after the Closing
Date, (ii) if the Warrant Shares are not covered under the Initial

 

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Registration Statement, use commercially reasonable efforts to either (A) cause
a Registration Statement on Form S-3 (or other appropriate form) covering the
resale of all of the Warrant Shares not already covered by an existing and
effective Registration Statement for an offering to be made on a continuous
basis pursuant to Rule 415 or, if Rule 415 is not available for offers and sales
of the Registrable Securities, by such other means of distribution of
Registrable Securities as the Investors may reasonably specify to be filed with
the Commission (the “Warrant Registration Statement”) or (B) file a
post-effective amendment to the Initial Registration Statement or other
Registration Statement covering the Warrant Shares, in either case, promptly
following stockholder approval, if necessary, of the requisite increase in the
Company’s Common Stock to cover the exercise of the Warrant Shares.

Following the Registration Statement being declared effective by the SEC, the
Company shall file with the SEC in accordance with Rule 424 under the Securities
Act the final prospectus contained in such Registration Statement.

Notwithstanding the registration obligations set forth in this Section 2(a), in
the event the Commission informs the Company that all of the Registrable
Securities, Shares and/or Warrant Shares, cannot, as a result of the application
of Rule 415, be registered for resale as a secondary offering on a single
Registration Statement, the Company agrees to promptly (i) inform each of the
Investors thereof and use its commercially reasonable efforts to file amendments
to the Initial Registration Statement as required by the Commission and/or
(ii) withdraw the Initial Registration Statement and/or Warrant Share
Registration Statement and file a new Registration Statement (a “New
Registration Statement”), in either case covering the maximum number of
Registrable Securities permitted to be registered by the Commission, on Form S-3
or such other form available to register for resale the Registrable Securities
as a secondary offering; provided, however, that prior to filing such amendment
or New Registration Statement, the Company shall be obligated to use its
commercially reasonable efforts to advocate with the Commission for the
registration of all of the Registrable Securities in accordance with any
publicly-available written or oral guidance, comment, requirements or requests
of the Commission staff and the Securities Act (collectively, the “SEC
Guidance”), including without limitation, the Manual of Publicly Available
Telephone Interpretations D.29. Notwithstanding any other provision of this
Agreement, if any SEC Guidance sets forth a limitation of the number of
Registrable Securities permitted to be registered on a particular Registration
Statement as a secondary offering (and notwithstanding that the Company used
diligent efforts to advocate with the Commission for the registration of all or
a greater number of Registrable Securities), unless otherwise directed in
writing by an Investor as to its Registrable Securities, the number of
Registrable Securities to be registered on such Registration Statement will
first be reduced by Registrable Securities not acquired pursuant to the Purchase
Agreements (whether pursuant to registration rights or otherwise), second by
Registrable Securities represented by holders of Warrant Shares (applied, in the
case that some Warrant Shares may be registered, to the Investors on a pro rata
basis based on the total number of unregistered Warrant Shares held by such
Investors) and third by Registrable Securities represented by Shares (applied,
in the case that some Shares may be registered, to the Investors on a pro rata
basis based on the total number of unregistered Shares held by such Investors,
subject to a determination by the Commission that certain Investors must be
reduced first based on the number of Shares held by such Investors). In the
event the Company amends the Initial Registration Statement or the Warrant
Registration Statement or files a New Registration Statement, as the case may
be, under clauses (i) or (ii) above, the

 

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Company will use its commercially reasonable efforts to file with the
Commission, as promptly as allowed by Commission or SEC Guidance provided to the
Company or to registrants of securities in general, one or more Registration
Statements on Form S-3 or such other form available to register for resale those
Registrable Securities that were not registered for resale on the Initial
Registration Statement or Warrant Registration Statement, both as amended, or
the New Registration Statement (the “Remainder Registration Statements”).

Subject to this Section 2(a), the Company will include in such registration (and
any related qualifications including compliance with blue sky laws), and in any
underwriting involved therein, all Registrable Securities specified by any
Investor in a written request or requests to the Company, made within ten days
after the date of written notice of such registration from the Company to the
Investors. Each Investor agrees that it shall not be entitled to be named as a
selling securityholder in any Registration Statement or use a prospectus for
offers and resales of Registrable Securities at any time, unless such Investor
has returned to the Company a completed and signed Investor Suitability
Questionnaire and a response to any requests for further information by the
Company.

(b) Effectiveness of Registration. The Company shall use commercially reasonable
efforts to cause any Registration Statement to be declared effective by the
Commission no later than ninety (90) days after filing or one hundred twenty
(120) days in the event of a review by the staff of the Commission, and
(iii) use best efforts to keep such Registration Statement continuously
effective until the earlier of (A) one (1) year from the date of the closing of
the Purchase Agreements and (B) the date on which any Registrable Securities
held by the Investors may be sold in their entirety in a single transaction
pursuant to Rule 144.

(c) Expenses of Registration. All Registration Expenses incurred in connection
with the registration described in Section 2 shall be borne by the Company. All
other registration expenses, if any, shall be borne by the Investors pro rata on
the basis of the number of shares so registered or proposed to be so registered.

(d) Registration Procedures. The Company will keep each Investor advised in
writing as to the initiation of the registration described in Section 2(a) and
as to the completion thereof. The Company will:

(i) Registration Statements. Prepare and file with the Commission the
Registration Statements with respect to such Registrable Securities and cause
such Registration Statements to become effective and remain effective, in each
case in accordance with the timeframes provided in Sections 2(a)-(b).

(ii) Amendments and Supplements. Prepare and file with the Commission such
amendments and supplements to such Registration Statements and the prospectus
used in connection with such Registration Statements as may be necessary to
comply with the provisions of the Securities Act with respect to the disposition
of all securities covered by such Registration Statements for the period set
forth in Section 2(b) above.

(iii) Prospectus. Furnish to the Investors such number of copies of the
Registration Statements, any amendments thereto, any documents incorporated by
reference

 

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therein, a prospectus, including a preliminary prospectus, in conformity with
the requirements of the Securities Act, and such other documents as they may
reasonably request in order to facilitate the disposition of Registrable
Securities owned by them, which disposition by the Investors shall be in
compliance with the Registration Statement and applicable federal and state
securities laws; provided that the Company shall have no obligation to provide
any document pursuant to this clause that is available on the Commission’s EDGAR
system.

(iv) Qualification. Use commercially reasonable efforts to register and qualify
the securities covered by such Registration Statements under such other
securities or blue sky laws of such jurisdictions as shall be reasonably
requested by the Investors; provided that the Company shall not be required in
connection therewith or as a condition thereto to qualify to do business or to
file a general consent to service of process in any such states or
jurisdictions, unless the Company is already subject to service in such
jurisdiction and except as may be required by the Securities Act.

(v) Underwriting Obligations. In the event of any underwritten public offering
of Registrable Securities, enter into and perform its obligations under an
underwriting agreement, in usual and customary form, with the managing
underwriter(s) of such offering. Each Investor participating in such
underwriting shall also enter into and perform its obligations under such an
underwriting agreement. The Company shall, if requested by the managing
underwriter or underwriters, if any, counsel to Investors, or any holder of
Registrable Securities included in such offering, promptly incorporate in a
prospectus supplement or post-effective amendment such information as such
managing underwriter or underwriters, counsel to Investors or any holder of
Registrable Securities reasonably requests to be included therein, and which is
reasonably related to the offering of such Registrable Securities, including,
without limitation, with respect to the Registrable Securities being sold by
such holder to such underwriter or underwriters, the purchase price being paid
therefor by such underwriter or underwriters and any other terms of an
underwritten offering of the Registrable Securities to be sold in such offering,
and the Company shall promptly make all required filings of such prospectus
supplement or post-effective amendment.

(vi) Notice. Immediately notify each Investor holding Registrable Securities
covered by a Registration Statement at any time when a prospectus relating
thereto is required to be delivered under the Securities Act of the happening of
any event as a result of which the prospectus included in such Registration
Statement, as then in effect, includes an untrue statement of a material fact or
omits to state a material fact required to be stated therein or necessary to
make the statements therein not misleading in light of the circumstances then
existing (a “Suspension Notice”); provided, however, that (i) the Company shall
not give more than two Suspension Notices during any period of twelve
consecutive months, (ii) any such Suspension Notice shall not be given within
120 days of the end of the Suspension Notice period under the prior Suspension
Notice and (iii) in no event shall the period from the date on which any holder
of Registrable Securities receives a Suspension Notice until the date on which
such holder receives copies of the supplemented or amended prospectus or is
advised in writing by the Company that the use of the prospectus may be resumed
exceed for all Suspension Notices in the aggregate, 60 days in any 365 day
period. The Company will use commercially reasonable efforts to promptly amend
or supplement such prospectus in order to cause such prospectus not to include
any untrue statement of a material fact or omit to state a material fact
required to be

 

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stated therein or necessary to make the statements therein not misleading in the
light of the circumstances then existing.

(vii) Listing. Cause all such Registrable Securities registered pursuant hereto
to be listed on each securities exchange or automated quotation system on which
similar securities issued by the Company are then listed.

(viii) Stop Orders. Use commercially reasonable efforts to prevent the issuance
of any order suspending the effectiveness of a Registration Statement relating
to Registrable Securities, and if one is issued, use commercially reasonable
efforts to obtain the withdrawal of any order suspending the effectiveness of
such Registration Statement at the earliest possible moment.

(ix) Company Records. Upon reasonable notice, make available to each Investor,
any underwriter participating in any disposition pursuant to a Registration
Statement relating to Registrable Securities, and any attorney, accountant or
other agent or representative retained by any such Investor or underwriter
(collectively, the “Inspectors”), all financial and other records, pertinent
corporate documents and properties of the Company (collectively, the “Records”)
reasonably necessary to enable them to exercise their due diligence
responsibility, and cause the Company’s officers, directors and employees to
supply all information requested by any such Inspector in connection with such
Registration Statement, provided that each such Investor and Inspector has
entered into a customary confidentiality agreement with respect to such Records.

(x) NASD Matters. Cooperate with each Investor and each underwriter
participating in the disposition of Registrable Securities and their respective
counsel in connection with any filings required to be made with the National
Association of Securities Dealers, Inc. (“NASD”), including, if appropriate, the
pre-filing of a prospectus as part of a Registration Statement in advance of an
underwritten offering.

(e) Indemnification.

(i) Company Indemnification. The Company will indemnify each Investor who holds
Registrable Securities (if Registrable Securities held by such Investor are
included in the securities as to which such registration is being effected),
each of its officers and directors and partners, and each person controlling
such Investor within the meaning of Section 15 of the Securities Act, with
respect to which registration has been effected pursuant to this Agreement,
against all expenses, claims, losses, damages or liabilities (or actions in
respect thereof), including any of the foregoing incurred in settlement of any
litigation, commenced or threatened, arising out of or based on any untrue
statement (or alleged untrue statement) of a material fact contained in any
Registration Statement, prospectus, offering circular or other document, or any
amendment or supplement thereto, incident to any such registration, or based on
any omission (or alleged omission) to state therein a material fact required to
be stated therein or necessary to make the statements therein, in light of the
circumstances in which they were made, not misleading, or any violation by the
Company of the Securities Act, the Exchange Act, state securities laws or any
rule or regulation promulgated under such laws applicable to the Company in
connection with any such registration, and the Company will reimburse each such

 

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Investor, each of its officers and directors, and each person controlling such
Investor, for any legal and any other expenses reasonably incurred, as such
expenses are incurred, in connection with investigating, preparing or defending
any such claim, loss, damage, liability or action, provided that the Company
will not be liable in any such case to the extent that any such claim, loss,
damage, liability or expense arises out of or is based on (A) any untrue
statement or omission or alleged untrue statement or omission made in reliance
upon and in conformity with written information furnished to the Company by an
instrument duly executed by such Investor or controlling person, and stated to
be specifically for use therein, (B) the use by Investor of an outdated or
defective prospectus after the Company has notified such Investor in writing
that the prospectus is outdated or defective or (C) Investor’s (or any other
indemnified person’s) failure to send or give a copy of the prospectus or
supplement (as then amended or supplemented), if required, pursuant to Rule 172
under the Securities Act (or any successor rule) to the Persons asserting an
untrue statement or alleged untrue statement or alleged untrue statement or
omission or alleged omission at or prior to the written confirmation of the sale
of Registrable Securities to such person if such statement or omission was
corrected in such prospectus or supplement; provided, further, that the
indemnity agreement contained in this subsection 2(e)(i) shall not apply to
amounts paid in settlement of any such loss, claim, damage, liability or action
if such settlement is effected without the consent of the Company (which consent
shall not be unreasonably withheld).

(ii) Investor Indemnification. Each Investor holding Registrable Securities
will, if Registrable Securities held by such Investor are included in the
securities as to which such registration is being effected, severally and not
jointly, indemnify the Company, each of its directors and officers, other
holders of the Company’s securities covered by such Registration Statement, each
person who controls the Company within the meaning of Section 15 of the
Securities Act, and each such holder, each of its officers and directors and
each person controlling such holder within the meaning of Section 15 of the
Securities Act, against all claims, losses, damages and liabilities (or actions
in respect thereof) arising out of or based on any untrue statement (or alleged
untrue statement) of a material fact contained in any such Registration
Statement, prospectus, offering circular or other document, or any omission (or
alleged omission) to state therein a material fact required to be stated therein
or necessary to make the statements therein not misleading, or any violation by
such holder of the Securities Act, the Exchange Act, state securities laws or
any rule or regulation promulgated under such laws applicable to such Investor,
and will reimburse the Company, each other holder, and directors, officers,
persons, underwriters or control persons of the Company and the other holders
for any legal or any other expenses reasonably incurred, as such expenses are
incurred, in connection with investigating or defending any such claim, loss,
damage, liability or action, but in the case of the Company or such other
holders or their officers, directors or controlling persons, only to the extent
that such untrue statement (or alleged untrue statement) or omission (or alleged
omission) is made in such Registration Statement, prospectus, offering circular
or other document in reliance upon and in conformity with written information
furnished to the Company by an instrument duly executed by such Investor and
stated to be specifically for use therein; provided, further, that the indemnity
agreement contained in this Subsection 2(e)(ii) shall not apply to amounts paid
in settlement of any such loss, claim, damage, liability or action if such
settlement is effected without the consent of such indemnifying Investor (which
consent shall not be unreasonably withheld or delayed). The liability of any
Investor for indemnification under this

 

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Section 2(e) in its capacity as a seller of Registrable Securities shall not
exceed the amount of net proceeds to such Investor of the securities sold in any
such registration.

(iii) Notice and Procedure. Each party entitled to indemnification under this
Section 2(e) (the “Indemnified Party”) shall give written notice to the party
required to provide indemnification (the “Indemnifying Party”) promptly after
such Indemnified Party has actual knowledge of any claim as to which indemnity
may be sought, and shall permit the Indemnifying Party to assume the defense of
any such claim or any litigation resulting therefrom, provided that counsel for
the Indemnifying Party, who shall conduct the defense of such claim or
litigation, shall be approved by the Indemnified Party (whose approval shall not
unreasonably be withheld), and the Indemnified Party may participate in such
defense at such party’s expense, and provided further that the failure of any
Indemnified Party to give notice as provided herein shall not relieve the
Indemnifying Party of its obligations under this Agreement unless the failure to
give such notice is materially prejudicial to an Indemnifying Party’s ability to
defend such action and provided further, that the Indemnifying Party shall not
assume the defense for matters as to which there is a conflict of interest or
there are separate and different defenses. No Indemnifying Party, in the defense
of any such claim or litigation, shall, except with the consent of each
Indemnified Party (whose consent shall not be unreasonably withheld), consent to
entry of any judgment or enter into any settlement which does not include as an
unconditional term thereof the giving by the claimant or plaintiff to such
Indemnified Party of a release from all liability in respect to such claim or
litigation.

(iv) Contribution. If the indemnification provided for in this Section 2(e) is
held by a court of competent jurisdiction to be unavailable to an Indemnified
Party with respect to any losses, claims, damages or liabilities referred to
herein, the Indemnifying Party, in lieu of indemnifying such Indemnified Party
thereunder, shall to the extent permitted by applicable law contribute to the
amount paid or payable by such Indemnified Party as a result of such loss,
claim, damage or liability in such proportion as is appropriate to reflect the
relative fault of the Indemnifying Party on the one hand and of the Indemnified
Party on the other in connection with the untrue statement or omission that
resulted in such loss, claim, damage or liability, as well as any other relevant
equitable considerations. The relative fault of the Indemnifying Party and of
the Indemnified Party shall be determined by a court of law by reference to,
among other things, whether the untrue or alleged untrue statement of a material
fact or the omission to state a material fact relates to information supplied by
the Indemnifying Party or by the Indemnified Party and the parties’ relative
intent, knowledge, access to information and opportunity to correct or prevent
such statement or omission; provided, that in no event shall any contribution by
an Investor hereunder exceed the proceeds from the offering received by such
Investor. The amount paid or payable by a party as a result of any loss, claim,
damage or liability shall be deemed to include, subject to the limitations set
forth in this Agreement, 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 2(e) was available to such party in
accordance with its terms.

(v) Survival. The obligations of the Company and the Investors under this
Section 2(e) shall survive completion of any offering of Registrable Securities
in a Registration Statement and the termination of this Agreement. The indemnity
and contribution

 

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agreements contained in this Section 2(e) are in addition to any liability that
the Indemnifying Parties may have to the Indemnified Parties and are not in
diminution or limitation of the indemnification provisions under the Purchase
Agreements.

(f) Information by Investor. Any Investor holding Registrable Securities
included in any Registration Statement shall furnish to the Company such
information regarding such Investor, the Registrable Securities held by such
Investor and the distribution proposed by such Investor as the Company may
request in writing and as shall be required in connection with any registration
referred to in this Agreement.

(g) Confidentiality. Each Investor agrees that any and all material, non-public
information received in connection with this Agreement shall remain confidential
to each Investor until such information otherwise becomes public, unless
disclosure by an Investor is required by law; and provided, further, that
notwithstanding each Investor’s agreement to keep such information confidential,
each such Investor makes no acknowledgement that any such information is
material, non-public information.

(h) Compliance. Each Investor covenants and agrees that it will (i) comply with
the prospectus delivery requirements of the Securities Act as applicable to it
(unless an exemption therefrom is available) in connection with sales of
Registrable Securities pursuant to the Registration Statement and shall sell the
Registrable Securities only in accordance with a method of distribution
described in the Registration Statement and will not transfer the Registrable
Securities without registration under the Securities Act or applicable state
securities laws or an exemption therefrom and (ii) shall not use an outdated or
defective prospectus after the Company has notified such Investor in writing
that the prospectus is outdated or defective.

3. Amendment. Except as otherwise provided herein, any provision of this
Agreement may be amended or the observance thereof may be waived (either
generally or in a particular instance and either retroactively or
prospectively), only with the written consent of the Company and Investors
holding a majority of the then-outstanding Registrable Securities. Any amendment
or waiver effected in accordance with this Section 3 shall be binding upon each
Investor, any transferee thereof and the Company.

4. Governing Law. This Agreement shall be governed in all respects by the
internal laws of the State of Delaware without regard to conflict of laws
provisions.

5. Entire Agreement. This Agreement constitutes the full and entire
understanding and Agreement among the parties regarding the matters set forth
herein. Except as otherwise expressly provided herein, the provisions hereof
shall inure to the benefit of, and be binding upon the successors, assigns,
heirs, executors and administrators of the parties hereto.

6. Severability. If any provision of this Agreement is held to be invalid or
unenforceable in any respect, the validity and enforceability of the remaining
terms and provisions of this Agreement shall not in any way be affected or
impaired thereby and the parties will attempt to agree upon a valid and
enforceable provision that is a reasonable substitute therefor, and upon so
agreeing, shall incorporate such substitute provision in this Agreement.

 

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7. Successors and Assigns. Except as otherwise expressly provided herein, the
provisions hereof shall inure to the benefit of, and be binding upon, the
Company’s and each Investor’s successors, assigns and transferees, including,
without limitation and without the need for an express assignment, subsequent
holders of Registrable Securities. If any assignee or transferee of any Investor
shall acquire Registrable Securities in any manner, whether by operation of law
or otherwise, such Registrable Securities shall be held subject to all of the
terms of this Agreement, and by taking and holding such Registrable Securities
such person shall be deemed to have agreed to be bound by and to perform all of
the terms and provisions of this Agreement and such person shall be entitled to
receive the benefits hereof.

8. Notices. All notices and other communications required or permitted hereunder
shall be in writing and shall be mailed by registered or certified mail, postage
prepaid, or otherwise delivered by facsimile transmission, by hand or by
messenger, addressed:

(a) Investor. If to an Investor, at such Investor’s address as set forth in the
Purchase Agreement, or at such other address as such Investor shall have
furnished to the Company.

(b) Company. If to the Company, to:

Arrowhead Research Corporation

201 South Lake Avenue, Suite 703

Pasadena, California 91101

Attention: President;

Facsimile number 626-792-5554

or at such other address as the Company shall have furnished to the Investors,
with a copy (which shall not constitute notice) to Goodwin Procter LLP, Three
Embarcadero Center, 24th Floor, Attn.: Ryan Murr.

Each such notice or other communication shall for all purposes of this Agreement
be treated as effective or having been given when delivered if delivered
personally, if sent by facsimile, the first business day after the date of
confirmation that the facsimile has been successfully transmitted to the
facsimile number for the party notified, or, if sent by mail, at the earlier of
its receipt or 72 hours after the same has been deposited in a regularly
maintained receptacle for the deposit of the United States mail, addressed and
mailed as aforesaid.

9. Counterparts. This Agreement may be executed by facsimile, in any number of
counterparts, each of which shall be an original and all of which together shall
constitute one instrument.

10. Specific Performance. The parties hereto specifically acknowledge that
monetary damages are not an adequate remedy for violations of this Agreement,
and that any party hereto may, in its sole discretion, apply to a court of
competent jurisdiction for specific performance or injunctive or such other
relief as such court may deem just and proper in order to enforce this Agreement
or prevent any violation hereof and, to the extent permitted by applicable

 

10

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law and to the extent the party seeking such relief would be entitled to the
merits to obtain such relief, each party waives any objection to the imposition
of such relief.

11. Designation of Forum and Consent to Jurisdiction. The parties hereto
(i) designate the courts of the State of Delaware as the forum where all matters
pertaining to this Agreement may be adjudicated, and (ii) by the foregoing
designation, consent to the exclusive jurisdiction and venue of such courts for
the purpose of adjudicating all matters pertaining to this Agreement.

12. Stock Split. All references to numbers of shares in this Agreement shall be
appropriately adjusted to reflect any stock dividend, split, combination or
other recapitalization of shares by the Company occurring after the date of this
Agreement.

13. Independent Nature of Investors’ Obligations and Rights. The obligations of
each Investor hereunder are several and not joint with the obligations of any
other Investor hereunder, and no Investor shall be responsible in any way for
the performance of the obligations of any other Investor hereunder. The decision
of each Investor to purchase Units pursuant to the Purchase Agreements has been
made independently of any other Investor. Nothing contained herein or in any
other agreement or document delivered at any closing, and no action taken by any
Investor pursuant hereto or thereto, shall be deemed to constitute the Investors
as a partnership, an association, a joint venture or any other kind of entity,
or create a presumption that the Investors are in any way acting in concert with
respect to such obligations or the transactions contemplated by this Agreement.
Each Investor shall be entitled to protect and enforce its rights, including
without limitation the rights arising out of this Agreement, and it shall not be
necessary for any other Investor to be joined as an additional party in any
proceeding for such purpose. The Company acknowledges that each of the Investors
has been provided with the same Registration Rights Agreement for the purpose of
closing a transaction with multiple Investors and not because it was required to
do so by any Investor.

[Signature Page to follow]

 

11

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IN WITNESS WHEREOF, the parties hereto have executed this Registration Rights
Agreement as of the date first set forth above.

 

ARROWHEAD RESEARCH CORPORATION

By:  

 

Name:  

 

Title:  

 

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IN WITNESS WHEREOF, the parties hereto have executed this Registration Rights
Agreement as of the date first set forth above.

 

INVESTOR

 

Name of Investor: By:  

 

Name:  

 

Title: