EXECUTION VERSION
STOCK PURCHASE AGREEMENT

THIS STOCK PURCHASE AGREEMENT (“Agreement”) is entered into as of February 26,
2020 (the “Execution Date”), by and between Biogen MA, Inc., a corporation
organized under the laws of the Commonwealth of Massachusetts having an office
at 225 Binney Street, Cambridge, MA 02142 (“Biogen”), and Sangamo Therapeutics,
Inc., a Delaware corporation having an office at 7000 Marina Blvd., Brisbane, CA
94005 (“Sangamo”). The capitalized terms used herein and not otherwise defined
have the meanings given to them in Appendix 1.
RECITALS
Sangamo has agreed to sell, and Biogen has agreed to purchase, shares of Common
Stock subject to and in accordance with the terms and provisions of this
Agreement.
AGREEMENT
For good and valuable consideration, the Parties agree as follows:
Section 1.SALE AND PURCHASE OF STOCK 
1.1 Purchase of Stock. . Subject to the terms and conditions of this Agreement,
at the Closing, Sangamo will issue and sell to Biogen, and Biogen will purchase
from Sangamo, 24,420,157 shares of Common Stock (the “Shares”) at a price per
share of $9.2137 for an aggregate purchase price of $225,000,000.00 (the
“Purchase Price”).
1.2 Payment. At the Closing, Biogen will pay the Purchase Price by wire transfer
of immediately available funds in accordance with wire instructions provided by
Sangamo to Biogen at least three (3) Business Days prior to the Closing, and
Sangamo will deliver the Shares in book-entry form to Biogen.
1.3 Closing.
(a) Closing. The closing of the transaction contemplated by Section 1.1 (the
“Closing”) will be held at the offices of Sangamo within three (3) Business Days
after the conditions to closing set forth in Section 7 are satisfied or waived
for the Closing (other than those conditions that by their nature are to be
satisfied or waived at the Closing) or at such other place, time and/or date as
may be jointly designated by Biogen and Sangamo for the Closing.
(b) Closing Deliverables.
(i) At the Closing, Sangamo will deliver to Biogen:
(1) a duly executed cross-receipt in form and substance reasonably satisfactory
to each party (the “Cross-Receipt”);
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(2) a certificate in form and substance reasonably satisfactory to Biogen and
duly executed on behalf of Sangamo by an authorized officer of Sangamo,
certifying that the conditions to Closing set forth in Section 7.2 of this
Agreement have been fulfilled; and
(3) a certificate of the secretary of Sangamo dated as of the Closing Date
certifying that attached thereto is a true and complete copy of all resolutions
adopted by the Board authorizing the execution, delivery and performance of this
Agreement and the Collaboration Agreement and the transactions contemplated
respectively therein and that all such resolutions are in full force and effect
and are all the resolutions adopted in connection with the transactions
contemplated hereby as of the Closing Date.
(ii) At the Closing, Biogen will deliver to Sangamo:
(1) a duly-executed Cross-Receipt; and
(2) a certificate in form and substance reasonably satisfactory to Sangamo and
duly executed on behalf of Biogen by an authorized officer of Biogen, certifying
that the conditions to Closing set forth in Section 7.1 of this Agreement have
been fulfilled.
Section 2. REPRESENTATIONS AND WARRANTIES OF SANGAMO 
Except as otherwise specifically contemplated by this Agreement, Sangamo hereby
represents and warrants to Biogen that:
2.1 Private Placement. Neither Sangamo nor any person acting on its behalf, has,
directly or indirectly, made any offers or sales of any security or solicited
any offers to buy any security, under any circumstances that would require
registration of the Shares under the Securities Act. Subject to the accuracy of
the representations made by Biogen in Section 3, the Shares will be issued and
sold to Biogen in compliance with applicable exemptions from the registration
and prospectus delivery requirements of the Securities Act and the registration
and qualification requirements of all applicable securities laws of the states
of the United States. Sangamo has not engaged any brokers, finders or agents, or
incurred, or will incur, directly or indirectly, any liability for brokerage or
finder’s fees or agents’ commissions or any similar charges in connection with
this Agreement and the transactions contemplated hereby.
2.2 Organization and Qualification. Sangamo is duly incorporated, validly
existing and in good standing under the laws of the State of Delaware, with full
corporate power and authority to conduct its business as currently conducted.
Sangamo is duly qualified to do business and is in good standing in every
jurisdiction in which the nature of the business conducted by it or property
owned by it makes such qualification necessary, except where the failure to be
so qualified or in good standing, as the case may be, would not reasonably be
expected to have a Material Adverse Effect on Sangamo.
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2.3 Authorization; Enforcement. Sangamo has all requisite corporate power and
authority to enter into and to perform its obligations under this Agreement, to
consummate the transactions contemplated hereby and to issue the Shares in
accordance with the terms hereof. The execution, delivery and performance of
this Agreement by Sangamo and the consummation by it of the transactions
contemplated hereby (including the issuance of the Shares at the Closing in
accordance with the terms hereof and, in connection with such issuance, any
actions taken with respect to Sangamo’s stock incentive plans or the shares of
Common Stock reserved thereunder) have been duly authorized by the Board and no
further consent or authorization of Sangamo, the Board, or its stockholders is
required. This Agreement has been duly executed by Sangamo and constitutes a
legal, valid and binding obligation of Sangamo enforceable against Sangamo in
accordance with its terms, except as enforceability may be limited by applicable
bankruptcy, insolvency, reorganization, or moratorium or similar laws affecting
creditors’ and contracting parties’ rights generally and except as
enforceability may be subject to general principles of equity and except as
rights to indemnity and contribution may be limited by state or federal
securities laws or public policy underlying such laws.
2.4 Issuance of Shares. The Shares are duly authorized and, upon issuance in
accordance with the terms of this Agreement, will be validly issued, fully paid
and non-assessable and will not be subject to preemptive rights or other similar
rights of stockholders of Sangamo.
2.5 SEC Documents, Financial Statements.
(a) The Common Stock is registered pursuant to Section 12(b) or 12(g) of the
Exchange Act. Sangamo has delivered or made available (by filing on the SEC's
electronic data gathering and retrieval system (EDGAR)) to Biogen complete
copies of its most recent Annual Report on Form 10-K and its most recent
Quarterly Report on Form 10-Q, and any report on Form 8-K, in each case filed
with the SEC after January 1, 2019 and prior to the Execution Date (the “SEC
Documents”). As of its date, each SEC Document complied in all material respects
with the requirements of the Exchange Act, and other federal, state and local
laws, rules and regulations applicable to it, and, as of its date, such SEC
Document did not contain any untrue statement of a material fact or omit to
state a material fact required to be stated therein or necessary in order to
make the statements therein, in light of the circumstances under which they were
made, not misleading.
(b) The financial statements, together with the related notes and schedules, of
Sangamo included in the SEC Documents comply as to form in all material respects
with all applicable accounting requirements and the published rules and
regulations of the SEC and all other applicable rules and regulations with
respect thereto. Such financial statements, together with the related notes and
schedules, have been prepared in accordance with GAAP applied on a consistent
basis during the periods involved (except (i) as may be otherwise indicated in
such financial statements or the notes thereto or (ii) in the case of unaudited
interim statements, to the extent they may not include footnotes
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or may be condensed or summary statements), and fairly present in all material
respects the financial condition of Sangamo and its consolidated subsidiaries as
of the dates thereof and the results of operations and cash flows for the
periods then ended (subject, in the case of unaudited statements, to normal
year-end audit adjustments).
(c) The Common Stock is listed on Nasdaq, and Sangamo has taken no action
designed to, or which to its knowledge is likely to have the effect of,
terminating the registration of the Common Stock under the Exchange Act or
delisting the Common Stock from Nasdaq. As of the date of this Agreement,
Sangamo has not received any notification that, and has no knowledge that, the
SEC or Nasdaq is contemplating terminating such registration or listing.
2.6 Internal Controls; Disclosure Controls and Procedures. Sangamo maintains
internal control over financial reporting as defined in Rule 13a-15(f) under the
Exchange Act. Sangamo has implemented the “disclosure controls and procedures”
(as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act) required in
order for the principal executive officer and principal financial officer of
Sangamo to engage in the review and evaluation process mandated by the Exchange
Act, and is in compliance with such disclosure controls and procedures in all
material respects. Each of the principal executive officer and the principal
financial officer of Sangamo has made all certifications required by Sections
302 and 906 of the Sarbanes-Oxley Act of 2002 with respect to all reports,
schedules, forms, statements and other documents required to be filed by Sangamo
with the SEC.
2.7 Capitalization and Voting Rights
(a) The authorized capital of Sangamo as of the date hereof consists of:
(i) 160,000,000 shares of Common Stock of which, as of February 25, 2020, (x)
116,173,820 shares were issued and outstanding, (y) 4,986,088 shares were
reserved for issuance pursuant to Sangamo’s stock incentive plans, and (z)
14,936,474 shares were issuable upon the exercise of stock options outstanding
or issuable upon vesting of restricted stock unit awards outstanding, and (ii)
5,000,000 shares of Preferred Stock, of which no shares are issued and
outstanding as of the date of this Agreement. All of the issued and outstanding
shares of Common Stock (A) have been duly authorized and validly issued, (B) are
fully paid and non-assessable and (C) were issued in material compliance with
all applicable federal and state securities laws and not in violation of any
preemptive rights.
(b) All of the authorized shares of Common Stock are entitled to one (1) vote
per share.
(c) Except as described or referred to in the SEC Documents, as of February 25,
2020, there were not: (i) any outstanding equity securities, options, warrants,
rights (including conversion or preemptive rights) or other agreements pursuant
to which Sangamo is or may become obligated to issue, sell or repurchase any
shares of its capital stock or any other securities of Sangamo other than equity
securities that may
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have been granted pursuant to its stock incentive plans, which plans are
described in the SEC Documents, or (ii) any restrictions on the transfer of
capital stock of Sangamo other than pursuant to federal or state securities laws
or as set forth in this Agreement.
(d) Sangamo is not a party to or subject to any agreement or understanding
relating to the voting of shares of capital stock of Sangamo or the giving of
written consents by a stockholder or director of Sangamo.
2.8 No Conflicts; Government Consents and Permits.
(a) The execution, delivery and performance of this Agreement by Sangamo and the
consummation by Sangamo of the transactions contemplated hereby (including the
issuance of the Shares) will not (i) conflict with or result in a violation of
any provision of Sangamo’s Certificate of Incorporation or Bylaws, (ii) violate
or conflict with, or result in a breach of any provision of, or constitute a
default under, any agreement, indenture, or instrument to which Sangamo is a
party, or (iii) result in a violation of any law, rule, regulation, order,
judgment or decree (including United States federal and state securities laws
and regulations and regulations of any self-regulatory organizations) applicable
to Sangamo, except in the case of clauses (ii) and (iii) only, for such
conflicts, breaches, defaults, and violations as would not reasonably be
expected to have a Material Adverse Effect on Sangamo or result in a liability
for Biogen.
(b) Sangamo is not required to obtain any consent, authorization or order of, or
make any filing or registration with, any court or governmental agency or any
regulatory or self regulatory agency in order for it to execute, deliver or
perform any of its obligations under this Agreement in accordance with the terms
hereof, or to issue and sell the Shares in accordance with the terms hereof
other than such as have been made or obtained, and except for (i) any
post-closing filings required to be made under federal or state securities laws,
(ii) any required filings or notifications regarding the issuance or listing of
additional shares with Nasdaq, and (iii) any consent required under the HSR Act.
2.9 Litigation. Other than as set forth in the SEC Documents filed prior to the
date of this Agreement, there is no action, suit, proceeding or investigation
pending (of which Sangamo has received notice or otherwise has knowledge) or, to
Sangamo’s knowledge, threatened, against Sangamo or which Sangamo intends to
initiate, except where such action, suit, proceeding or investigation, as the
case may be, would not reasonably be expected to have a Material Adverse Effect.
2.10 Licenses and Other Rights; Compliance with Laws. Sangamo has all
franchises, permits, licenses and other rights and privileges (“Permits”)
necessary to permit it to own its properties and to conduct its business as
presently conducted and is in compliance thereunder, except where the failure to
be in compliance would not reasonably be expected to have a Material Adverse
Effect. To Sangamo’s knowledge, Sangamo has not taken any action that would
interfere with its ability to renew all such Permit(s), except where the failure
to renew such Permit(s) would not reasonably be
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expected to have a Material Adverse Effect. Sangamo is and has been in
compliance with all laws applicable to its business, properties and assets, and
to the products and services sold by it, except where the failure to be in
compliance has not had and would not reasonably be expected to have a Material
Adverse Effect.
2.11 Intellectual Property.
(a) The Intellectual Property that is owned by Sangamo or its subsidiaries is
owned free from any liens or restrictions. To Sangamo’s knowledge, all of
Sangamo’s material Intellectual Property Licenses are in full force and effect
in accordance with their terms, are free of any liens or restrictions, and
neither Sangamo, nor any other party thereto, is in material breach of any such
material Intellectual Property License. To Sangamo’s knowledge (i) no event has
occurred that with notice or lapse of time or both would constitute a breach or
default of any such material Intellectual Property License or (ii) would result
in the termination thereof, or (iii) would cause or permit the acceleration or
other change of any right or obligation or the loss of any benefit thereunder by
Sangamo or its subsidiaries except (1) in the case of each of (i)-(iii) as would
not reasonably be expected to have a Material Adverse Effect, or (2) as set
forth in any such Intellectual Property License. Except as set forth in the SEC
Documents, to Sangamo’s knowledge, there is no legal claim or demand of any
person or any proceeding that is pending or overtly threatened in writing, (i)
challenging the right of Sangamo in respect of any Intellectual Property of
Sangamo, or (ii) claiming that any default exists under any Intellectual
Property License, except, in the case of (i) and (ii) above, where any such
claim, demand or proceeding has not had and would not reasonably be expected to
have a Material Adverse Effect.
(b) Except as set forth in the SEC Documents: (i) Sangamo or one of its
subsidiaries owns, free and clear of any lien or encumbrance, or, to Sangamo’s
knowledge, has a valid license , or an enforceable right to use, as it is used
or held for use, all U.S. and non-U.S. patents, trade secrets, know-how,
trademarks, service marks, copyrights, and other proprietary and intellectual
property rights, and all grants and applications with respect to the foregoing
(collectively, the “Proprietary Rights”) necessary for the conduct of Sangamo’s
business, except where the failure to own or have any of the foregoing would not
reasonably be expected to have a Material Adverse Effect (such Proprietary
Rights owned by or licensed to Sangamo collectively, the “Sangamo Rights”); and
(ii) to Sangamo’s knowledge, Sangamo and its subsidiaries have taken reasonable
measures to protect the Sangamo Rights, consistent with prudent commercial
practices in the biotechnology industry, except where failure to take such
measures has not had and would not reasonably be expected to have a Material
Adverse Effect.
2.12 Absence of Certain Changes.
(a) Except as disclosed in the SEC Documents filed prior to the Execution Date,
since September 30, 2019, no change or event has occurred, except where such
change or event has not and would not reasonably be expected to have a Material
Adverse Effect on Sangamo.
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(b) Except as set forth in the SEC Documents filed prior to the Execution Date
or as contemplated by this Agreement or the Collaboration Agreement, since
September 30, 2019, Sangamo has not (i) declared or paid any dividends, or
authorized or made any distribution upon or with respect to any class or series
of its capital stock, or (ii) sold, exchanged or otherwise disposed of any of
its material assets or rights.
(c) Since September 30, 2019, Sangamo has not admitted in writing its inability
to pay its debts generally as they become due, filed or consented to the filing
against it of a petition in bankruptcy or a petition to take advantage of any
insolvency act, made an assignment for the benefit of creditors, consented to
the appointment of a receiver for itself or for the whole or any substantial
part of its property, or had a petition in bankruptcy filed against it, been
adjudicated a bankrupt, or filed a petition or answer seeking reorganization or
arrangement under the federal bankruptcy laws or any other laws of the United
States or any other jurisdiction.
2.13 Not an Investment Company. Sangamo is not, and solely after receipt of the
Purchase Price, will not be, an “investment company” as defined in the
Investment Company Act of 1940, as amended.
2.14 No Integration. Sangamo has not, directly or through any agent, sold,
offered for sale, solicited offers to buy or otherwise negotiated in respect of,
any security (as defined in the Securities Act) which is or will be integrated
with the Shares sold pursuant to this Agreement in a manner that would require
the registration of the Shares under the Securities Act.
Section 3. REPRESENTATIONS AND WARRANTIES OF BIOGEN 
Except as otherwise specifically contemplated by this Agreement, Biogen hereby
represents and warrants to Sangamo that:
3.1 Authorization; Enforcement. Biogen has the requisite corporate power and
authority to enter into this Agreement and to consummate the transactions
contemplated hereby. Biogen has taken all necessary corporate action to
authorize the execution, delivery and performance of this Agreement. Upon the
execution and delivery of this Agreement, this Agreement will constitute a valid
and binding obligation of Biogen enforceable against Biogen in accordance with
its terms, except as enforceability may be limited by applicable bankruptcy,
insolvency, reorganization, moratorium or similar laws affecting creditors’ and
contracting parties’ rights generally and except as enforceability may be
subject to general principles of equity and except as rights to indemnity and
contribution may be limited by state or federal securities laws or public policy
underlying such laws.
3.2 No Conflicts; Government Consents and Permits.
(a) The execution, delivery and performance of this Agreement by Biogen and the
consummation by Biogen of the transactions contemplated hereby (including the
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purchase of the Shares) will not (i) conflict with or result in a violation of
any provision of Biogen’s Certificate of Incorporation or Bylaws, (ii) violate
or conflict with, or result in a breach of any provision of, or constitute a
default under, any agreement, indenture, or instrument to which Biogen is a
party, or (iii) result in a violation of any law, rule, regulation, order,
judgment or decree (including United States federal and state securities laws
and regulations and regulations of any self-regulatory organizations) applicable
to Biogen, except in the case of clauses (ii) and (iii) only, for such
conflicts, breaches, defaults, and violations as would not reasonably be
expected to have a Material Adverse Effect on Biogen or result in a liability
for Sangamo.
(b) Biogen is not required to obtain any consent, authorization or order of, or
make any filing or registration with, any court or governmental agency or any
regulatory or self regulatory agency in order for it to execute, deliver or
perform any of its obligations under this Agreement in accordance with the terms
hereof, or to purchase the Shares in accordance with the terms hereof other than
such as have been made or obtained except for any consent required under the HSR
Act.
3.3 Investment Purpose. Biogen is purchasing the Shares for its own account and
not with a present view toward the public distribution thereof and has no
arrangement or understanding with any other persons regarding the distribution
of such Shares except as would not result in a violation of the Securities Act.
Biogen will not, directly or indirectly, offer, sell, pledge, transfer or
otherwise dispose of (or solicit any offers to buy, purchase or otherwise
acquire or take a pledge of) any of the Shares except in accordance with the
Securities Act and to the extent permitted by Section 6.1 and Section 6.2.
3.4 Reliance on Exemptions. Biogen understands that Sangamo intends for the
Shares to be offered and sold to it in reliance upon specific exemptions from
the registration requirements of United States federal and state securities laws
and that Sangamo is relying upon the truth and accuracy of, and Biogen’s
compliance with, the representations, warranties, agreements, acknowledgments
and understandings of Biogen set forth herein in order to determine the
availability of such exemptions and the eligibility of Biogen to acquire the
Shares.
3.5 Accredited Investor; Access to Information. Biogen is an “accredited
investor” as defined in Regulation D under the Securities Act and is
knowledgeable, sophisticated and experienced in making, and is qualified to make
decisions with respect to investments in shares presenting an investment
decision like that involved in the purchase of the Shares. Biogen has been
furnished with materials relating to the offer and sale of the Shares, that have
been requested by Biogen, including, without limitation, Sangamo’s SEC
Documents, and Biogen has had the opportunity to review the SEC Documents.
Biogen has been afforded the opportunity to ask questions of Sangamo. Neither
such inquiries nor any other investigation conducted by or on behalf of Biogen
or its representatives or counsel will modify, amend or affect Biogen's right to
rely on the truth, accuracy and completeness of the SEC Documents and Sangamo’s
representations
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and warranties contained in this Agreement. Biogen has, with respect to all
matters relating to this Agreement and the offer and sale of the Shares, not
relied upon counsel.
3.6 Governmental Review. Biogen understands that no United States federal or
state agency or any other government or governmental agency has passed upon or
made any recommendation or endorsement of the Shares or an investment therein.
Section 4. STANDSTILL AGREEMENT.  
4.1 Prior to the earlier of (x) the three-year anniversary of the Effective Date
and (y) the date that Biogen beneficially owns less than 5% of the Common Stock
(the “Standstill Period”), Biogen and its Affiliates will not, directly or
indirectly, except as expressly approved or invited by Sangamo.
(a) effect or seek, offer or propose (whether publicly or otherwise) to effect,
or cause or participate in or in any way advise, assist or encourage any other
person to effect or seek, offer or propose (whether publicly or otherwise) to
effect or participate in, (i) any acquisition of any securities (or beneficial
ownership thereof) or material assets of Sangamo, (ii) any tender or exchange
offer, merger, or other business combination involving Sangamo, (iii) any
recapitalization, restructuring, liquidation, dissolution or other extraordinary
transaction with respect to Sangamo, or (iv) any “solicitation” of “proxies” (as
such terms are used in the proxy rules of the SEC) or consents to vote any
voting securities of Sangamo;
(b) form, join or in any way participate in a “group” (as defined under the
Exchange Act) with respect to any securities of Sangamo;
(c) otherwise act, alone or in concert with others, to seek to control or
influence the management, Board or policies of Sangamo;
(d) take any action that would reasonably be expected to require Sangamo to make
a public announcement regarding any of the types of matters set forth in clause
(a) above; or
(e) enter into any discussions or arrangements with any person with respect to
any of the foregoing.
4.2 Biogen also agrees during the Standstill Period not to request Sangamo (or
its representatives), directly or indirectly, to amend or waive any provision of
this Section 4, other than by means of a confidential communication to the
Sangamo Chairman of the Board or Chief Executive Officer. Biogen represents and
warrants that, as of the Execution Date, neither Biogen nor any of its
Affiliates owns, of record or beneficially, any voting securities of Sangamo, or
any securities convertible into or exercisable for any voting securities of
Sangamo.
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4.3 Notwithstanding the provisions set forth in Sections 4.1 and 4.2 (the
“Standstill Provisions”), Biogen shall immediately, and without any other action
by Sangamo, be released from its obligations under the Standstill Provisions if:
(a) Sangamo executes a definitive agreement with a third party providing for an
acquisition (by way of merger, tender offer or otherwise), of more than 50% of
Sangamo’s outstanding Common Stock or all or substantially all of Sangamo’s
assets, then (in any of such cases), (b) a third party commences a tender offer
seeking to acquire beneficial ownership of more than 50% of Sangamo’s
outstanding Common Stock and the Board recommends that the stockholders tender
their Common Stock in such tender offer (with any acquisition described in (a)
and (b) referred to as a “Change of Control Transaction”), or (c) Sangamo waives
any standstill or similar provision in any other agreement between Sangamo and a
third party for the explicit purpose of allowing the third party to engage in
any Change of Control Transaction. None of (x) the ownership nor purchase by an
employee benefit plan of Biogen or Biogen’s Affiliates in any diversified index,
mutual or pension fund managed by an independent advisor, which fund in-turn
holds, directly or indirectly, securities of Sangamo, (y) transfers or resales
of the Shares by Biogen to any other person in compliance with Section 6 or (z)
the mere voting of the Shares in accordance with Section 5, will be deemed to be
a breach of Biogen’s standstill obligations under this Section 4.
4.4 As the Effective Date, all prior standstill agreements between Biogen and
Sangamo are terminated and of no further force and effect, including but not
limited to that certain Standstill Agreement dated February 19, 2020 by and
between Biogen and Sangamo.
Section 5. VOTING AGREEMENT.  
5.1 Voting Agreement.
(a) If the Proxyholder instructs Biogen in writing to vote in favor of, or
against, any matter, action, ratification or other event for which approval of
the holders of Sangamo’s stock is sought (either by vote or written consent) or
upon which such holders are otherwise entitled to vote, including but not
limited to the election of directors, but excluding any Extraordinary Matter
(collectively, a “Sangamo Stockholder Matter”), then Biogen will (i) after
receiving proper notice of any meeting of stockholders of Sangamo related to
such Sangamo Stockholder Matter (or, if no notice is required or such notice is
properly waived, after notice from the Proxyholder is given), be present, in
person or by proxy, as a holder of Shares at all such meetings and be counted
for the purposes of determining the presence of a quorum at such meetings and
(ii) vote (in person, by proxy or by action by written consent, as applicable)
all Shares as to which Biogen has beneficial ownership or as to which Biogen
otherwise exercises voting or dispositive authority in the manner directed by
the Proxyholder.
(b) Extraordinary Matters. Biogen may vote or execute a written consent with
respect to, any or all of the voting securities of Sangamo as to which they are
entitled to vote or execute a written consent, as it may determine in its sole
discretion,
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with respect to the following matters, if presented to Sangamo’s stockholders
for approval (each such matter being an “Extraordinary Matter”):
(i) any transaction which would result in a Change of Control of Sangamo;
(ii) any issuance of Common Stock that represents more than 20% of the then
outstanding Common Stock;
(iii) the entry into any licensing, partnering, partnership, collaboration,
research and development, joint venture or other commercial agreement;
(iv) the payment of any dividends to any class of stockholders of Sangamo; and
(v) any liquidation or dissolution of Sangamo.
(c) Appointment of Proxy. To secure Biogen’s obligations to vote the Shares in
accordance with this Agreement and to comply with the other terms hereof, Biogen
hereby appoints the Proxyholder, or his designees, as Biogen’s true and lawful
proxy and attorney, with the power to act alone and with full power of
substitution, to vote or act by written consent with respect to all of Biogen’s
Shares in accordance with the provisions set forth in this Agreement, and to
execute all appropriate instruments consistent with this Agreement on behalf of
Biogen. The proxy and power granted by Biogen pursuant to this Section 5 are
coupled with an interest and are given to secure the performance of Biogen’s
duties under this Agreement. Each such proxy and power will be irrevocable until
the agreements contained in this Section 5 expire in accordance with Section
5.1(e). The proxy and power will survive the merger, consolidation, conversion
or reorganization of Biogen or any other entity holding any Shares (other than
any Shares sold by Biogen in compliance with Section 6). For the avoidance of
doubt, the proxy granted by this Section 5 shall not apply to any Extraordinary
Matter.
(d) No Revocation. The voting agreements contained in this Section 5 are coupled
with an interest and may not be revoked prior to their expiration in accordance
with Section 5.1(e).
(e) Expiration. The agreements contained in this Section 5 will expire (i) in
part, solely with respect to any Shares sold by Biogen in an arm’s length sale
to a non-Affiliate in compliance with this Agreement upon the execution of the
sale of such Shares, and (ii) as a whole on the earlier of (1) the two-year
anniversary of the Effective Date, (2) the date that Biogen beneficially owns
less than 5% of the Common Stock, and (3) the date the Collaboration Agreement
is terminated; provided, however, that in no event shall such expiration date be
prior to the one-year anniversary of the Effective Date. For the avoidance of
doubt, the agreements contained in this Section 5 shall not limit Biogen’s
ability to transfer or resell any Shares, provided that such transfers or
resales are done in accordance with Section 6.
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Section 6. TRANSFER, RESALE, LEGENDS.  
6.1 Transfer or Resale. Biogen understands that:
(a) the Shares have not been and are not being registered under the Securities
Act or any applicable state securities laws and, consequently, Biogen may have
to bear the risk of owning the Shares for an indefinite period of time because
the Shares may not be transferred unless (i) the resale of the Shares is
registered pursuant to an effective registration statement under the Securities
Act, including pursuant to the registration rights set forth in Section 6.5 and
Appendix 2; (ii) Biogen has delivered to Sangamo an opinion of counsel (in form,
substance and scope customary for opinions of counsel in comparable
transactions) to the effect that the Shares to be sold or transferred may be
sold or transferred pursuant to an exemption from such registration; or (iii)
the Shares are sold or transferred pursuant to Rule 144; and
(b) any sale of the Shares made in reliance on Rule 144 may be made only in
accordance with the terms of Rule 144 and, if Rule 144 is not applicable, any
resale of the Shares under circumstances in which the seller (or the person
through whom the sale is made) may be deemed to be an underwriter (as that term
is defined in the Securities Act) may require compliance with some other
exemption under the Securities Act or the rules and regulations of the SEC
thereunder.
6.2 Lock-Up. Biogen agrees that it will hold and will not sell any of the Shares
(or otherwise make any short sale of, grant any option for the purchase of, or
enter into any hedging or similar transaction with the same economic effect as a
sale of the Shares) until the one-year anniversary of the Effective Date (the
“Initial Holding Period”). Biogen further agrees that from the one-year
anniversary of the Effective Date through the two-year anniversary of the
Effective Date, inclusive, (the “Partial Holding Period” and together with the
Initial Holding Period, the “Holding Periods”), Biogen will hold and will not
sell at least 50% of the Shares (or otherwise make any short sale of, grant any
option for the purchase of, or enter into any hedging or similar transaction
with the same economic effect as a sale of the Shares). In addition, after the
expiration of the Initial Holding Period, in any single trading day Biogen will
not sell an amount of Shares that exceeds 10% of the average daily trading
volume of the Common Stock on Nasdaq over the five (5) trading day period ending
on the trading day immediately prior to such trading date (the “Volume
Limitation”). Notwithstanding the foregoing, this Section 6.2 will not preclude,
and the Volume Limitation shall not apply to, sales of Shares by Biogen (i) to a
third party pursuant to a tender offer made by such third party, or (ii) as part
of an underwritten offering after Biogen exercises any of its registration
rights as set forth in Appendix 2.
6.3 Legends. Biogen understands the Shares will bear a restrictive legend in
substantially the following form (and a stop-transfer order may be placed
against transfer of the Shares):
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THE SHARES EVIDENCED HEREBY ARE SUBJECT TO AN AGREEMENT TO VOTE THESE SHARES IN
THE MANNER SET FORTH IN THE STOCK PURCHASE AGREEMENT DATED FEBRUARY 26, 2020
BETWEEN SANGAMO THERAPEUTICS, INC. AND BIOGEN MA, INC.
THE SALE, PLEDGE, HYPOTHECATION OR TRANSFER OF THESE SECURITIES IS SUBJECT TO
THE TERMS AND CONDITIONS OF A STOCK PURCHASE AGREEMENT DATED FEBRUARY 26, 2020
BETWEEN SANGAMO THERAPEUTICS, INC. AND BIOGEN MA, INC.
If such Shares may be transferred pursuant to Section 6.2, Biogen may request
that Sangamo remove, and Sangamo agrees to authorize and instruct (including by
causing any required legal opinion to be provided) the removal of any legend
from the Shares, if permitted by applicable securities law, within two (2)
Business Days of any such request; provided, however, each party will be
responsible for any fees it incurs in connection with such request and removal.
6.4 10b5-1 Plan. If requested by Biogen, Sangamo will approve and adopt, without
unreasonable delay or condition, any written plan by Biogen for trading the
Shares that is designed in accordance with Rule 10b5-1(c) of the Exchange Act,
as long as such plan does not violate this Agreement (including but not limited
to the Standstill and Lock-Up provisions) and applicable securities laws.
6.5 Registration Rights. Sangamo hereby provides Biogen with the registration
rights set forth on Appendix 2 attached hereto, which is hereby incorporated in
and made a part of this Agreement as if set forth in full herein.
Section 7. CONDITIONS TO CLOSING 
7.1 Conditions to Obligations of Sangamo. Sangamo’s obligation to complete the
purchase and sale of the Shares and deliver the Shares to Biogen is subject to
the fulfillment or waiver of the following conditions at or prior to the
Closing:
(a) Receipt of Funds. Sangamo will have received immediately available funds in
the full amount of the Purchase Price for the Shares being purchased hereunder.
(b) Representations and Warranties. The representations and warranties made by
Biogen in Section 3 will be true and correct in all material respects as of the
Closing Date, except to the extent such representations and warranties are made
as of another date, in which case such representations and warranties will be
true and correct in all material respects as of such other date.
(c) Covenants. All covenants and agreements contained in this Agreement to be
performed or complied with by Biogen on or prior to the Closing Date shall have
been performed or complied with in all material respects.
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(d) Absence of Litigation. No proceeding challenging this Agreement or the
transactions contemplated hereby, or seeking to prohibit, alter, prevent or
materially delay the Closing, will have been instituted or be pending before any
court, arbitrator, governmental body, agency or official.
(e) No Governmental Prohibition; HSR Clearance. The sale of the Shares by
Sangamo and the purchase of the Shares by Biogen will not be prohibited by any
applicable law or governmental order or regulation. Each of the HSR Conditions
under the Collaboration Agreement shall have been satisfied.
(f) Collaboration Agreement. Biogen shall have duly executed and delivered the
Collaboration Agreement to Sangamo, and subject to execution by Biogen, such
agreement shall be in full force and effect.
(g) Closing Deliverables. All closing deliverables as required under
Section 1.3(b) shall have been delivered by Biogen to Sangamo.
7.2 Conditions to Biogen’s Obligations at the Closing. Biogen’s obligation to
complete the purchase and sale of the Shares is subject to the fulfillment or
waiver of the following conditions at or prior to the Closing:
(a) Representations and Warranties. The representations and warranties made by
Sangamo in Section 2, except for the representations and warranties made by
Sangamo in Sections 2.9, 2.10, 2.11 and 2.12(a), will be true and correct in all
material respects as of the Closing Date, except to the extent such
representations and warranties are made as of another date, in which case such
representations and warranties will be true and correct in all material respects
as of such other date.
(b) Covenants. All covenants and agreements contained in this Agreement to be
performed or complied with by Sangamo on or prior to the Closing Date shall have
been performed or complied with in all material respects.
(c) Transfer Agent Instructions. Sangamo will have delivered to its transfer
agent irrevocable written instructions to issue the Shares to Biogen in a form
and substance acceptable to such transfer agent.
(d) Nasdaq Qualification. Nasdaq shall have raised no objection to the
consummation of the transactions contemplated by this Agreement in the absence
of stockholder approval of such transactions.
(e) Absence of Litigation. No proceeding challenging this Agreement or the
transactions contemplated hereby, or seeking to prohibit, alter, prevent or
materially delay the Closing, will have been instituted or be pending before any
court, arbitrator, governmental body, agency or official.
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(f) Collaboration Agreement. Sangamo shall have duly executed and delivered the
Collaboration Agreement to Biogen, and subject to execution by Sangamo, such
agreement shall be in full force and effect.
(g) No Governmental Prohibition; HSR Clearance. The sale of the Shares by
Sangamo, and the purchase of the Shares by Biogen will not be prohibited by any
applicable law or governmental order or regulation. Each of the HSR Conditions
under the Collaboration Agreement shall have been satisfied.
(h) Closing Deliverables. All closing deliverables as required under
Section 1.3(b) shall have been delivered by Sangamo to Biogen.
Section 8. TERMINATION.
8.1 Ability to Terminate. This Agreement may be terminated:
(a) at any time by mutual written consent of Sangamo and Biogen;
(b) by Sangamo, upon written notice to Biogen, so long as Sangamo is not then in
breach of its representations, warranties, covenants or agreements under this
Agreement such that any of the conditions set forth in Section 7.1, as
applicable, could not be satisfied by the Termination Date, (i) upon a breach of
any covenant or agreement on the part of Biogen set forth in this Agreement, or
(ii) if any representation or warranty of Biogen shall have been or become
untrue, in each case such that any of the conditions set forth in Section 7.1
could not be satisfied by the Termination Date;
(c) by Biogen, upon written notice to Sangamo, so long as Biogen is not then in
breach of its representations, warranties, covenants or agreements under this
Agreement such that any of the conditions set forth in Section 7.2, as
applicable, could not be satisfied by the Termination Date, (i) upon a breach of
any covenant or agreement on the part of Sangamo set forth in this Agreement, or
(ii) if any representation or warranty of Sangamo shall have been or become
untrue, in each case such that any of the conditions set forth in Section 7.2
could not be satisfied by the Termination Date.
(d) by either Sangamo or Biogen, upon written notice to the other, if the
Closing has not occurred on or before the outside date set forth in Section 15.3
of the Collaboration Agreement (the “Termination Date”). In such event, neither
party shall have any further obligations under this Agreement.
8.2 Automatic Termination. In the event that the Collaboration Agreement is
terminated prior to the “Effective Date” thereof (as such term is defined in the
Collaboration Agreement), this Agreement shall terminate automatically.
8.3 Effect of Termination. In the event of the termination of this Agreement
pursuant to Section 8.1 or Section 8.2, (a) this Agreement (except for this
Section 8.3, Section 9 and Section 1.5 of Appendix 2, and any definitions set
forth in this Agreement
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and used in such Sections) shall forthwith become void and have no effect,
without any liability on the part of any party hereto or its Affiliates, and (b)
all filings, applications and other submissions made pursuant to this Agreement,
to the extent practicable, shall be withdrawn from the agency or other person to
which they were made or appropriately amended to reflect the termination of the
transactions contemplated hereby; provided, however, that nothing contained in
this Section 8.3 shall relieve any party from liability for fraud or any
intentional or willful breach of this Agreement.
Section 9. GOVERNING LAW; MISCELLANEOUS.  
9.1 Governing Law; Jurisdiction. This Agreement will be governed by and
interpreted in accordance with the laws of the State of Delaware without regard
to the principles of conflict of laws.
9.2 HSR Clearance; Market Listing.
(a) Each of Biogen and Sangamo agree that any required filings with the U.S.
Federal Trade Commission and the U.S. Department under the HSR Act with respect
to the transactions contemplated hereby and by the Collaboration Agreement shall
be governed by Section 15.2 (HSR Filing) of the Collaboration Agreement.
(b) From the Execution Date through the Closing, Sangamo shall use commercially
reasonable efforts to (a) maintain the listing and trading of the Common Stock
on Nasdaq and (b) effect the listing of the Shares on Nasdaq.
9.3 Counterparts; Electronic Signatures. This Agreement may be executed in two
counterparts, both of which are considered one and the same agreement and will
become effective when the counterparts have been signed by each party and
delivered to the other party hereto. This Agreement, once executed by a party,
may be delivered to the other party hereto by electronic PDF of a copy of this
Agreement bearing the signature of the party so delivering this Agreement.
9.4 Headings. The headings of this Agreement are for convenience of reference
only, are not part of this Agreement and do not affect its interpretation.
9.5 Severability. If any provision of this Agreement should be held invalid,
illegal or unenforceable in any jurisdiction, the parties will negotiate in good
faith a valid, legal and enforceable substitute provision that most nearly
reflects the original intent of the parties and all other provisions hereof will
remain in full force and effect in such jurisdiction and will be liberally
construed in order to carry out the intentions of the parties hereto as nearly
as may be possible. Such invalidity, illegality or unenforceability will not
affect the validity, legality or enforceability of such provision in any other
jurisdiction.
9.6 Entire Agreement; Amendments. This Agreement (including any schedules and
exhibits hereto) constitutes the entire agreement between the parties hereto
with
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respect to the subject matter hereof and thereof. There are no restrictions,
promises, warranties or undertakings, other than those set forth or referred to
herein or therein. This Agreement supersedes all prior agreements and
understandings between the parties hereto with respect to the subject matter
hereof. No provision of this Agreement may be waived or amended other than by an
instrument in writing signed by the party to be charged with enforcement. Any
amendment or waiver effected in accordance with this Section 9.6 will be binding
upon Biogen and Sangamo.
9.7 Notices. All notices required or permitted hereunder will be in writing and
will be deemed effectively given: (a) upon personal delivery to the party to be
notified, (b) when sent by confirmed email if sent during normal business hours
of the recipient, if not, then on the next Business Day, or (c) one Business Day
after deposit with a nationally recognized overnight courier, specifying next
day delivery, with written verification of receipt. The addresses for such
communications are:
If to Sangamo, addressed to:  Sangamo Therapeutics, Inc.
         7000 Marina Blvd.
         Brisbane, CA 94005
         Attention: Chief Financial Officer
         E-mail: SungLee@sangamo.com

with copies to:  Sangamo Therapeutics, Inc.
         7000 Marina Blvd.
         Brisbane, CA 94005
         Attention: General Counsel
         E-mail: GLoeb@sangamo.com

         Cooley LLP
101 California Street, 5th Floor  San Francisco, CA 94111-5800
         Attention: Robert W. Phillips
         E-mail: rphillips@cooley.com

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If to Biogen, addressed to:  Biogen MA, Inc.
         225 Binney Street
         Cambridge, MA 02142
Attention: Chief Legal Officer  E-mail: legaldepartment@biogen.com

with a copy to:  Ropes & Gray LLP
         Prudential Tower
         800 Boylston Street
         Boston, MA 02199-360
         Attention: Zachary Blume
         E-mail: Zachary.Blume@ropesgray.com

9.8 Successors and Assigns. This Agreement is binding upon and inures to the
benefit of the parties and their successors and assigns. Sangamo will not assign
this Agreement or any rights or obligations hereunder without the prior written
consent of Biogen, and Biogen will not assign this Agreement or any rights or
obligations hereunder without the prior written consent of Sangamo; provided,
however, that Biogen may assign this Agreement together with all of the Shares
it then owns (subject to Section 4 and Section 5) to any wholly-owned subsidiary
and any such assignee may assign the Agreement together with all of the Shares
it then owns (subject to Section 4 and Section 5) to Biogen or any other
subsidiary wholly-owned by Biogen, in any such case, without such consent
provided that the assignee agrees to assume Biogen’s obligations under Section 4
and Section 5 of this Agreement.
9.9 Third Party Beneficiaries. This Agreement is intended for the benefit of the
parties hereto, their respective permitted successors and assigns, and is not
for the benefit of, nor may any provision hereof be enforced by, any other
person.
9.10 Further Assurances; Survival. Each party will do and perform, or cause to
be done and performed, all such further acts and things, and will execute and
deliver all other agreements, certificates, instruments and documents, as the
other party may reasonably request in order to carry out the intent and
accomplish the purposes of this Agreement and the consummation of the
transactions contemplated hereby. The provisions of this Agreement will survive
termination.
9.11 No Strict Construction. The language used in this Agreement is deemed to be
the language chosen by the parties to express their mutual intent, and no rules
of strict construction will be applied against a party.
9.12 Equitable Relief. Sangamo recognizes that, if it fails to perform or
discharge any of its obligations under this Agreement, any remedy at law may
prove to be inadequate relief to Biogen. Sangamo therefore agrees that Biogen is
entitled to seek temporary and permanent injunctive relief or specific
performance in any such case. Biogen also recognizes that, if it fails to
perform or discharge any of its obligations under
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this Agreement, any remedy at law may prove to be inadequate relief to Sangamo.
Biogen therefore agrees that Sangamo is entitled to seek temporary and permanent
injunctive relief or specific performance in any such case.
9.13 Expenses. Sangamo and Biogen are each liable for, and will pay, their own
expenses incurred in connection with the negotiation, preparation, execution and
delivery of this Agreement, including, without limitation, attorneys’ and
consultants’ fees and expenses.

[Remainder of page intentionally left blank.]
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IN WITNESS WHEREOF, Biogen and Sangamo have caused this Agreement to be duly
executed as of the date first above written.
BIOGEN MA, INC.

By:        /s/ Michel Vounatsos

Its:       CEO

SANGAMO THERAPEUTICS, INC.

By:        /s/ Alexander Macrae

Its:        President + CEO

[Signature page to Stock Purchase Agreement]
Section 10. 
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APPENDIX 1
DEFINED TERMS
“Affiliate” of an entity means any corporation, firm, partnership or other
entity which directly or indirectly through one or more intermediaries controls,
is controlled by or is under common control with it. An entity will be deemed to
control another entity if it (i) owns, directly or indirectly, at least 50% of
the outstanding voting securities or capital stock (or such lesser percentage
which is the maximum allowed to be owned by a foreign corporation in a
particular jurisdiction) of such other entity, or has other comparable ownership
interest with respect to any entity other than a corporation; or (ii) has the
power, whether pursuant to contract, ownership of securities or otherwise, to
direct the management and policies of the entity.
“Board” means the board of directors of Sangamo.
“Business Day” means a day Monday through Friday on which banks are generally
open for business in the State of California.
“Change of Control” means with respect to a party, any (i) direct or indirect
acquisition or license of all or substantially all of the assets of such party,
(ii) direct or indirect acquisition by a person, or group of persons acting in
concert, of 50% or more of the voting equity interests of a party, (iii) tender
offer or exchange offer that results in any person, or group of persons acting
in concert, beneficially owning 50% or more of the voting equity interests of a
party, or (iv) merger, consolidation, other business combination or similar
transaction involving a party, pursuant to which any person owns all or
substantially all of the consolidated assets, net revenues or net income of a
party, taken as a whole, or which results in the holders of the voting equity
interests of a party immediately prior to such merger, consolidation, business
combination or similar transaction ceasing to hold 50% or more of the combined
voting power of the surviving, purchasing or continuing entity immediately after
such merger, consolidation, other business combination or similar transaction,
in all cases where such transaction is to be entered into with any person other
than the other party to this Agreement or its Affiliates.
“Closing Date” means the date on which the Closing actually occurs.
“Collaboration Agreement” means that certain Collaboration and License
Agreement, dated February 26, 2020, between Biogen, Biogen International GmbH
and Sangamo.
“Common Stock” means shares of Sangamo’s common stock, par value $0.01 per
share.
“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the
rules and regulations of the SEC thereunder.
“GAAP” means generally accepted accounting principles in the United States of
America as applied by Sangamo.
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“Governmental Authority” means any Federal, state, provincial, local, municipal,
foreign or other governmental or quasi-governmental authority, including without
limitation any arbitrator and applicable securities exchanges, or any
department, minister, agency, commission, commissioner, board, subdivision,
bureau, agency, instrumentality, court or other tribunal of any of the
foregoing.
“HSR Act” means Hart-Scott-Rodino Antitrust Improvements Act of 1976, as
amended.
“Intellectual Property” shall mean shall mean trademarks, trade names, trade
dress, service marks, copyrights, and similar rights (including registrations
and applications to register or renew the registration of any of the foregoing),
patents and patent applications, trade secrets, and any other similar
intellectual property rights.

“Intellectual Property License” shall mean any license, permit, authorization,
approval, contract or consent granted, issued by or with any person relating to
the use of Intellectual Property.
“Material Adverse Effect” means any change, effect or circumstance, individually
or in the aggregate, (a) that is reasonably likely to be materially adverse to
the business, operations, assets or financial condition of Sangamo or Biogen, as
the case may be, taken as a whole, or (b) that materially impairs the ability of
Sangamo or Biogen to perform its obligations pursuant to the transactions
contemplated by this Agreement or the Collaboration Agreement; provided however,
that, none of the following (alone or when aggregated any other effects), shall
be deemed to be a Material Adverse Effect, and none of the following (alone or
when aggregated any other effects), shall be taken into account for purposes of
clause (a) above: (A) (1) general market, economic or political conditions or
(2) conditions (or any changes therein) in the industries in which Sangamo or
Biogen conducts business, in each case, including any acts of terrorism or war,
weather conditions, global virus epidemics or other force majeure events, in the
case of each of (1) and (2), solely to the extent that such effects do not have
and are not reasonably likely to have a material disproportionate impact on
Sangamo or Biogen, as the case may be; (B) this Agreement, the Collaboration
Agreement and the transactions contemplated hereby and thereby; or (C) (1)
regulatory, manufacturing or clinical changes resulting from any studies
sponsored by Sangamo or Biogen, or clinical trial meetings (and communications
related thereto), and including, for the avoidance of doubt, any increased
incidence or severity of any side effects, adverse effects, adverse events or
safety observations (new or previously identified); (2) any determination (or
delay thereof), positive or negative, with respect to the acceptance, filing,
designation, approval, or clearance of any of Sangamo’s or Biogen’s products or
product candidates; (3) approval (or other clinical or regulatory developments),
market entry (or threat thereof) of competitive products, or any regulatory
guidance, announcement or publication relating to approval of any products or
product candidates of Sangamo or Biogen; or (4) changes in the trading price or
volume of the Common Stock or Biogen’s common stock, in and of themselves . The
capitalized terms used in this definition and not otherwise defined in this
Agreement have the meanings given to them in the Collaboration Agreement.
“Nasdaq” means The Nasdaq Global Select Market.
“Preferred Stock” means shares of Sangamo’s preferred stock, par value $0.01 per
share.
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“Proxyholder” means Sangamo Therapeutics, Inc. and its Chief Executive Officer
and/or Chief Operating Officer, in their capacities as such officers of Sangamo
Therapeutics, Inc.
“SEC” means the United States Securities and Exchange Commission or any
successor entity.
“Securities Act” means the Securities Act of 1933, as amended, and the rules and
regulations of the SEC thereunder.

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APPENDIX 2
REGISTRATION RIGHTS GRANTED BY SANGAMO TO BIOGEN
a.FORM S-3 REGISTRATION. Biogen may send Sangamo a written request (a “Biogen
S-3 Registration Request”) or requests that Sangamo effect a registration on
Form S-3 (or any successor to Form S-3) or any similar short-form registration
statement and any related qualification or compliance with respect to all or a
part of the Shares owned by Biogen, and in such case Sangamo will as soon as
practicable, effect such registration and all such qualifications and
compliances as may be so requested and as would permit or facilitate the sale
and distribution of all or such portion of Biogen’s Shares as are specified in
such request; provided, however, that Sangamo will not be obligated to effect
any such registration, qualification or compliance pursuant to this Section 1.1:
(a) if Form S-3 is not available for such offering by Biogen;
(b) if Biogen, together with the holders of any other securities of Sangamo
entitled to inclusion in such registration, propose to sell Shares and such
other securities (if any) at an aggregate price to the public of less than
$50,000,000;
(c) if within thirty (30) days of receipt of a written request from Biogen
pursuant to this Section 1.1, Sangamo gives notice to Biogen of Sangamo’s
intention to make a public offering within ninety (90) days, other than pursuant
to (i) a registration statement relating to any employee benefit plan, including
but not limited to any employee equity plan or employee stock purchase plan or
(ii) with respect to any corporate reorganization or transaction under Rule 145
of the Securities Act, any registration statements related to the issuance or
resale of securities issued in such a transaction or (iii) a registration
related to stock issued upon conversion of debt securities (any registration
statement described in clauses (i) – (iii), a “Special Registration Statement”);
provided, that such right to delay a request will be exercised by Sangamo not
more than once in any twelve month period;
(d) if Sangamo furnishes Biogen a certificate signed by the Chairman of the
Board of Directors of Sangamo stating that in the good faith judgment of
Sangamo’s Board of Directors, it would be seriously detrimental to Sangamo and
its stockholders for such Form S-3 registration to be effected at such time, in
which event Sangamo will have the right to defer the filing of the Form S-3
registration statement for a period of not more than ninety (90) days after
receipt of Biogen’s request under this Section 1.1; provided, that such right to
delay a request will be exercised by Sangamo not more than once in any twelve
month period;
(e) if Sangamo has (i) within the twelve month period preceding the date of such
request, already effected one registration or (ii) already effected two
registrations, in each case on Form S-3 for Biogen pursuant to this Section 1.1;
(f) for an underwritten public offering of Biogen’s Shares, if Biogen (i) has,
within the twelve month period preceding the date of such request, already
completed one underwritten public offering, or (ii) has completed more than two
underwritten public offerings
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of Biogen’s Shares; it being further understood and agreed that in connection
with any offering initiated by Biogen pursuant to this Section 1.1 involving an
underwriting of Biogen’s Shares, Sangamo shall not be required to perform its
obligations under this Section 1.1 unless (i) the underwriting banks are
mutually agreeable to Sangamo and Biogen, (ii) Biogen enters into an
underwriting agreement in customary form with the underwriter or underwriters,
(iii) Biogen accepts customary terms in such underwriting agreement with regard
to representations and warranties relating to ownership of the Biogen Shares and
authority and power to enter into such underwriting agreement and (iv) Biogen
completes and executes all questionnaires, powers of attorney, custody
agreements, indemnities and other documents as may be requested by such
underwriter or underwriters; it being further understood and agreed that Sangamo
shall not be required to perform its obligations under this Section 1.1. in such
underwriting if the underwriting agreement proposed by the underwriter or
underwriters contains representations, warranties or conditions that are not
reasonable in light of Sangamo’s then-current business; or
(g) in any particular jurisdiction in which Sangamo would be required to qualify
to do business or to execute a general consent to service of process in
effecting such registration, qualification or compliance.
(h) Subject to the foregoing, Sangamo will file a Form S-3 registration
statement covering the Shares requested by Biogen for registration as soon as
reasonably practicable after receipt of Biogen’s requests and Biogen’s
information pursuant to Section 1.4.
b.EXPENSES OF REGISTRATION. Sangamo will bear all Registration Expenses with
respect to the Shares incurred in connection with any registration,
qualification or compliance pursuant to Section 1.1. “Registration Expenses”
means all expenses incurred by Sangamo in complying with Section 1.1, including,
without limitation, all registration and filing fees, printing expenses, fees
and disbursements of Sangamo’s counsel, blue sky fees, and the expense of any
audits, comfort letters or consents incident to or required by any such
registration, and the fully-burdened full time equivalent rate of Sangamo’s
employees who conduct activities related to any registration or offering of
Shares under this Agreement. Biogen will bear the expenses of its own counsel
and any Selling Expenses based upon the sale of Shares owned by Biogen. “Selling
Expenses” means all underwriting discounts and selling commissions applicable to
an offering involving Shares registered pursuant to Section 1.1.
c.OBLIGATIONS OF SANGAMO. Whenever required to effect the registration of any
Shares, Sangamo will, as expeditiously as reasonably possible:
(a) prepare and file with the SEC a registration statement with respect to such
Shares and use all commercially reasonable efforts to cause such registration
statement to become effective, and, upon Biogen’s request, keep such
registration statement effective for up to thirty (30) days or, if earlier,
until Biogen has completed the distribution related thereto; provided, however,
that at any time, upon written notice to Biogen and for a period not to exceed
sixty (60) days thereafter (the “Suspension Period”), Sangamo may delay the
filing or effectiveness of any registration statement or suspend the use of any
registration statement (and Biogen hereby agrees not to offer or sell any Shares
pursuant to such registration statement during the Suspension Period) if (a)
Sangamo reasonably believes that there is or may be in
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existence material nonpublic information or events involving Sangamo, the
failure of which to be disclosed in the prospectus included in the registration
statement could result in a Violation (as defined below), (b) all reports
required to be filed by Sangamo pursuant to the Exchange Act have not been filed
by the required date (without regard to any extension), or (c) if the
consummation of any business combination by Sangamo has occurred or is probable
for purposes of Rule 3-05 or Article 11 of Regulation S-X promulgated by the SEC
or any similar successor rule. If Sangamo will exercise its right to delay the
filing or effectiveness or suspend the use of a registration hereunder, the
applicable time period during which the registration statement is to remain
effective will be extended by a period of time equal to the duration of the
Suspension Period. Sangamo may extend the Suspension Period for an additional
consecutive sixty (60) days with Biogen’s consent, which consent will not be
unreasonably withheld. If so directed by Sangamo, Biogen will (i) not offer to
sell any Shares pursuant to the registration statement during the period in
which the delay or suspension is in effect after receiving notice of such delay
or suspension; and (ii) use its commercially reasonable efforts to deliver to
Sangamo (at Sangamo’s expense) all copies, other than permanent file copies then
in Biogen’s possession, of the prospectus relating to such Shares current at the
time of receipt of such notice. Notwithstanding the foregoing, Sangamo will not
be required to file, cause to become effective or maintain the effectiveness of
any registration statement other than a registration statement on Form S-3 that
contemplates a distribution of securities on a delayed or continuous basis
pursuant to Rule 415 under the Securities Act.
(b) Prepare and file with the SEC such amendments and supplements to such
registration statement and the prospectus used in connection with such
registration statement 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 statement for the period set forth in subsection (a) above.
(c) Furnish Biogen such number of copies of a prospectus, including a
preliminary prospectus, in conformity with the requirements of the Securities
Act, and such other documents as it may reasonably request in order to
facilitate the disposition of the registered Shares.
(d) Use its commercially reasonable efforts to register and qualify the
securities covered by such registration statement under such other securities or
blue sky laws of such jurisdictions as will be reasonably requested by Biogen;
provided that Sangamo will 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.
(e) In the event of any underwritten public offering, enter into and perform its
obligations under an underwriting agreement, in usual and customary form, with
the managing underwriter(s) of such offering. Biogen will also enter into and
perform its obligations under such an agreement.
(f) With respect to Shares covered by such registration statement, notify Biogen
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
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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 the light of the
circumstances then existing. Sangamo will use commercially reasonable efforts to
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 stated therein or necessary to make the statements therein not
misleading in the light of the circumstances then existing.
(g) Use its commercially reasonable efforts to furnish, on the date that such
Shares are delivered to the underwriters for sale, if such securities are being
sold through underwriters, (i) an opinion, dated as of such date, of the counsel
representing Sangamo for the purposes of such registration, in form and
substance as is customarily given to underwriters in an underwritten public
offering, addressed to the underwriters, if any, and (ii) a letter, dated as of
such date, from the independent certified public accountants of Sangamo, in form
and substance as is customarily given by independent certified public
accountants to underwriters in an underwritten public offering addressed to the
underwriters.
d.FURNISHING INFORMATION.
(a) If Biogen requests to register any Shares pursuant to Section 1.1, Biogen
will furnish Sangamo such information regarding itself, the Shares held by it
and the intended method of disposition of such securities as will be required to
effect the registration of its Shares.
(b) Sangamo will have no obligation with respect to any registration requested
pursuant to Section 1.2 if the number of Shares or the anticipated aggregate
offering price of the securities to be registered thereunder does not equal or
exceed the number of shares or the anticipated aggregate offering price required
to originally trigger Sangamo’s obligation to initiate such registration as
specified in Section 1.1.
e.INDEMNIFICATION. If any Shares are included in a registration statement under
Section 1.1:
(a) To the extent permitted by law, Sangamo will indemnify and hold harmless
Biogen, its officers and directors, as applicable, any underwriter (as defined
in the Securities Act) for Biogen and each person, if any, who controls Biogen
or such underwriter within the meaning of the Securities Act or the Exchange
Act, against any losses, claims, damages, or liabilities (joint or several) to
which they may become subject under the Securities Act, the Exchange Act or
other federal or state law, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon any
of the following statements, omissions or violations (collectively a
“Violation”) by Sangamo: (i) any untrue statement or alleged untrue statement of
a material fact contained in such registration statement or incorporated by
reference therein, including any preliminary prospectus or final prospectus
contained therein or any amendments or supplements thereto, (ii) the 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 (iii) any
violation or alleged violation by Sangamo of the Securities Act, the Exchange
Act, any state securities law or any rule or regulation promulgated
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under the Securities Act, the Exchange Act or any state securities law in
connection with the offering covered by such registration statement; and Sangamo
will reimburse each such indemnified party for any legal or other expenses
reasonably incurred by them in connection with investigating or defending any
such loss, claim, damage, liability or action; provided however, that the
indemnity agreement contained in this Section 1.5(a) will not apply to amounts
paid in settlement of any such loss, claim, damage, liability or action if such
settlement is effected without Sangamo’s consent, which consent will not be
unreasonably withheld, nor will Sangamo be liable in any such case for any such
loss, claim, damage, liability or action to the extent that it arises out of or
is based upon a Violation which occurs in reliance upon and in conformity with
written information furnished expressly for use in connection with such
registration by any of such indemnified parties.
(b) To the extent permitted by law, Biogen will, if Shares are included in the
securities as to which such registration qualifications or compliance is being
effected, indemnify and hold harmless Sangamo, each of its directors, its
officers and each person, if any, who controls Sangamo within the meaning of the
Securities Act, and any underwriter and any other third party, as applicable,
selling securities under such registration statement, against any losses,
claims, damages or liabilities (joint or several) to which Sangamo or any such
director, officer, controlling person, underwriter or other third party who may
become subject under the Securities Act, the Exchange Act or other federal or
state law, insofar as such losses, claims, damages or liabilities (or actions in
respect thereto) arise out of or are based upon any of the following statements:
(i) any untrue statement or alleged untrue statement of a material fact
contained in such registration statement or incorporated reference therein,
including any preliminary prospectus or final prospectus contained therein or
any amendments or supplements thereto, (ii) the 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 (iii) any violation or alleged
violation by Sangamo of the Securities Act (collectively, a “Biogen Violation”),
in each case to the extent (and only to the extent) that such Biogen Violation
occurs in reliance upon and in conformity with written information furnished by
Biogen under an instrument duly executed by Biogen and stated to be specifically
for use in connection with such registration; and Biogen will reimburse any
legal or other expenses reasonably incurred by Sangamo or any such director,
officer, controlling person, underwriter or other third party in connection with
investigating or defending any such loss, claim, damage, liability or action if
it is judicially determined that there was such a Biogen Violation; provided,
however, that the indemnity agreement contained in this Section 1.5 will not
apply to amounts paid in settlement of any such loss, claim, damage, liability
or action if such settlement is effected without Biogen’s consent, which consent
will not be unreasonably withheld; provided further, that in no event will any
indemnity under this Section 1.5 exceed the net proceeds from the offering
received by Biogen, as applicable.
(c) Promptly after receipt by an indemnified party under this Section 1.5 of
notice of the commencement of any action (including any governmental action),
such indemnified party will, if a claim in respect thereof is to be made against
any indemnifying party under this Section 1.5, deliver to the indemnifying party
a written notice of the commencement thereof and the indemnifying party will
have the right to participate in, and, to the extent the indemnifying party so
desires, jointly with any other indemnifying party similarly noticed, to
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assume the defense thereof with counsel mutually satisfactory to the parties;
provided, however, that an indemnified party will have the right to retain its
own counsel, with the fees and expenses thereof to be paid by the indemnifying
party, if representation of such indemnified party by the counsel retained by
the indemnifying party would be inappropriate due to actual or potential
differing interests between such indemnified party and any other party
represented by such counsel in such proceeding. The failure to deliver written
notice to the indemnifying party within a reasonable time of the commencement of
any such action will relieve such indemnifying party of any liability to the
indemnified party under this Section 1.5 to the extent, and only to the extent,
prejudicial to its ability to defend such action, but the omission so to deliver
written notice to the indemnifying party will not relieve it of any liability
that it may have to any indemnified party otherwise than under this Section 1.5.
(d) If the indemnification provided for in this Section 1.5 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,
will 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 Violation(s) or Biogen Violation(s) 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 will 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 will any contribution by
Biogen hereunder exceed the net proceeds from the offering received by Biogen.
(e) The obligations of Sangamo and Biogen under this Section 1.5 will survive
completion of any offering of Shares, as applicable, in a registration statement
and, with respect to liability arising from an offering to which this Section
1.5 would apply that is covered by a registration filed before termination of
this Agreement, such termination. No indemnifying party, in the defense of any
such claim or litigation, will, except with the consent of each indemnified
party, 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.
f.ASSIGNMENT OF REGISTRATION RIGHTS. The rights to cause Sangamo to register
Shares pursuant to this Appendix 2 may be assigned by Biogen to a single
transferee or assignee of Shares (for so long as such registration rights remain
in effect) that (a) is an Affiliate of Biogen that is a corporation, partnership
or limited liability company, or (b) acquires all of Biogen’s Shares in
connection with the sale of all or substantially all of such Biogen’s business;
provided, however, (i) the transferor will, within ten (10) days after such
transfer, furnish Sangamo written notice of the name and address of such
transferee or assignee and the
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securities with respect to which such registration rights are being assigned and
(ii) such transferee will agree to be subject to all restrictions set forth in
this Agreement.
g. “MARKET STAND-OFF” AGREEMENT. Biogen hereby agrees that, if requested by the
underwriters in any offering in which Biogen includes Shares, it will execute a
customary lock-up agreement in connection with any Shares that are not included
in such underwritten offering.
h.AGREEMENT TO FURNISH INFORMATION. Biogen hereby agrees to execute and deliver
such other agreements as may be reasonably requested by Sangamo or the
underwriter that are consistent with Biogen’s obligations under Section 1.7, as
applicable, or that are necessary to give further effect thereto. In addition,
if requested by Sangamo or the representative of the underwriters of Common
Stock, Biogen will provide, within ten (10) days of such request, such
information as may be required by Sangamo or such representative in connection
with the completion of any public offering of Sangamo’s securities pursuant to a
registration statement filed under the Securities Act. The obligations described
in Section 1.7 and this Section 1.8 will not apply to a Special Registration
Statement. Sangamo may impose stop-transfer instructions with respect to the
shares of Common Stock (or other securities) subject to the foregoing
restriction until the end of said ten (10) day period. The underwriters of
Common Stock (or other securities) are intended third party beneficiaries of
Sections 1.7 and 1.8 and will have the right, power and authority to enforce the
provisions hereof as though they were a party hereto.
i.RULE 144 REPORTING. With a view to making available to Biogen the benefits of
certain rules and regulations of the SEC which may permit the sale of the Shares
to the public without registration, Sangamo agrees to use its reasonable best
efforts to:
(a) Make and keep public information available, as those terms are understood
and defined in SEC Rule 144 or any similar or analogous rule promulgated under
the Securities Act, at all times after the effective date of the first
registration filed by Sangamo for an offering of its securities to the general
public; and
(b) File with the SEC, in a timely manner, all reports and other documents
required of Sangamo under the Exchange Act.
j.TERMINATION OF REGISTRATION RIGHTS. Biogen’s right to request registration or
inclusion of Shares in any registration pursuant to Section 1.1 hereof will
terminate upon such time as all remaining Shares may be sold pursuant to Rule
144 during any ninety (90) day period.

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