EX-4.1



 Exhibit 4.1 

Execution Version 

FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 

THIS FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT (the “Agreement”) is made as of February 9, 2018, by
and among Evelo Biosciences, Inc., a Delaware corporation (the “Company”), and each of the investors listed on Schedule A hereto (each, an “Investor,” and together with any subsequent investors, or
transferees, who become parties hereto as “Investors” pursuant to Subsection 6.9, the “Investors”). 

WHEREAS, certain of the Investors (the “Existing Investors”) possess registration rights, information rights, rights
of first offer, and other rights pursuant to a Third Amended and Restated Investors’ Rights Agreement, dated as of January 5, 2017, among the Company and such Investors (the “Prior Agreement”); 

WHEREAS, the Existing Investors desire to amend and restate the Prior Agreement in its entirety and to accept the rights created
pursuant to this Agreement in lieu of the rights granted to them under the Prior Agreement; and 
 WHEREAS, concurrently with the
execution of this Agreement, the Company and certain of the Investors are entering into a Series C Preferred Stock Purchase Agreement (as the same may be amended and/or restated from time to time, the “Purchase Agreement”), pursuant
to which such Investors have agreed to purchase shares of Series C Preferred Stock (as defined below). 
 NOW, THEREFORE, the Company
and the Existing Investors hereby agree to amend and restate the Prior Agreement in its entirety as set forth herein, and all of the parties hereto further agree as follows: 

1. Definitions. For purposes of this Agreement: 

1.1 “Affiliate” means, with respect to any specified Person, any other Person who, directly or indirectly, controls, is
controlled by, or is under common control with such Person, including without limitation any general partner, managing member, officer or director of such Person or any venture capital or other investment fund now or hereafter existing that is
controlled by one or more general partners or managing members of, or shares the same management company or investment advisor with, such Person. 

1.2 “Common Stock” means shares of the Company’s common stock, par value $0.001 per share. 

1.3 “Damages” means any loss, damage, claim, or liability (joint or several) to which a party hereto may become subject under
the Securities Act, the Exchange Act, or other federal or state law, insofar as such loss, damage, claim, or liability (or any action in respect thereof) arises out of or is based upon (i) any untrue statement or alleged untrue statement of a
material fact contained in any registration statement of the Company, including any preliminary prospectus or final prospectus contained therein or any amendments or supplements thereto; (ii) an 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 the indemnifying party (or any of its agents or Affiliates) of the Securities Act, the
Exchange Act, any state securities law, or any rule or regulation promulgated under the Securities Act, the Exchange Act, or any state securities law. 







 1.4 “Derivative Securities” means any securities or rights convertible into, or
exercisable or exchangeable for (in each case, directly or indirectly), Common Stock, including options and warrants. 
 1.5
“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder. 

1.6 “Excluded Registration” means (i) a registration relating to the sale of securities to employees of the Company or a
subsidiary pursuant to a stock option, stock purchase, or similar plan; (ii) a registration relating to an SEC Rule 145 transaction; (iii) a registration on any form that does not include substantially the same information as would be
required to be included in a registration statement covering the sale of the Registrable Securities; or (iv) a registration in which the only Common Stock being registered is Common Stock issuable upon conversion of debt securities that are
also being registered. 
 1.7 “Form S-1” means such form under the Securities Act as
in effect on the date hereof or any successor registration form under the Securities Act subsequently adopted by the SEC. 
 1.8
“Form S-3” means such form under the Securities Act as in effect on the date hereof or any registration form under the Securities Act subsequently adopted by the SEC that permits incorporation
of substantial information by reference to other documents filed by the Company with the SEC. 
 1.9 “GAAP” means generally
accepted accounting principles in the United States. 
 1.10 “Holder” means any holder of Registrable Securities who is a
party to this Agreement. 
 1.11 “Immediate Family Member” means a child, stepchild, grandchild, parent, stepparent,
grandparent, spouse, sibling, mother-in-law, father-in-law, son-in-law, daughter-in-law,
brother-in-law or sister-in-law, including adoptive relationships, of a natural person
referred to herein. 
 1.12 “Initiating Holders” means, collectively, Holders who properly initiate a registration request
under this Agreement. 
 1.13 “IPO” means the Company’s first underwritten public offering of its Common Stock under
the Securities Act. 
 1.14 “Key Employee” means any executive-level employee (including division director and vice
president-level positions) as well as any employee who, either alone or in concert with others, develops, invents, programs, or designs any Company Intellectual Property (as defined in the Purchase Agreement). 

  
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 1.15 “Major Investor” means any Investor that, individually or together with
such Investor’s Affiliates, holds at least 862,068 shares of Series C Preferred Stock (as adjusted for any stock split, stock dividend, combination, or other recapitalization or reclassification effected after the date hereof). 

1.16 “New Securities” means, collectively, equity securities of the Company, whether or not currently authorized, as well as
rights, options, or warrants to purchase such equity securities, or securities of any type whatsoever that are, or may become, convertible or exchangeable into or exercisable for such equity securities. 

1.17 “Person” means any individual, corporation, partnership, trust, limited liability company, association or other entity.

 1.18 “Preferred Director” means any director of the Company that the holders of record of the Preferred Stock are
entitled to elect as a separate class pursuant to the Company’s Certificate of Incorporation. 
 1.19 “Preferred Stock”
means shares of Series A Preferred Stock, Series A-1 Preferred Stock, Series A-2 Preferred Stock, Series A-3 Preferred Stock,
Series B Preferred Stock and Series C Preferred Stock. 
 1.20 “Registrable Securities” means (i) the Common Stock
issuable or issued upon conversion of the Preferred Stock; (ii) any Common Stock, or any Common Stock issued or issuable (directly or indirectly) upon conversion and/or exercise of any other securities of the Company, held by the Investors as
of the date hereof or acquired by the Investors after the date hereof; and (iii) any Common Stock issued as (or issuable upon the conversion or exercise of any warrant, right, or other security that is issued as) a dividend or other
distribution with respect to, or in exchange for or in replacement of, the shares referenced in clause (i) and (ii) above; excluding in all cases, however, any Registrable Securities sold by a Person in a transaction in which the
applicable rights under this Agreement are not assigned pursuant to Subsection 6.1, and excluding for purposes of Section 2 any shares for which registration rights have terminated pursuant to Subsection 2.13
of this Agreement. 
 1.21 “Registrable Securities then outstanding” means the number of shares determined by adding the
number of shares of outstanding Common Stock that are Registrable Securities and the number of shares of Common Stock issuable (directly or indirectly) pursuant to then exercisable and/or convertible securities that are Registrable Securities. 

1.22 “Restricted Securities” means the securities of the Company required to be notated with the legend set forth in
Subsection 2.12(b) hereof. 
 1.23 “SEC” means the Securities and Exchange Commission. 

1.24 “SEC Rule 144” means Rule 144 promulgated by the SEC under the Securities Act. 

1.25 “SEC Rule 145” means Rule 145 promulgated by the SEC under the Securities Act. 

  
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 1.26 “Securities Act” means the Securities Act of 1933, as amended, and the
rules and regulations promulgated thereunder. 
 1.27 “Selling Expenses” means all underwriting discounts, selling
commissions, and stock transfer taxes applicable to the sale of Registrable Securities, and fees and disbursements of counsel for any Holder, except for the fees and disbursements of the Selling Holder Counsel borne and paid by the Company as
provided in Subsection 2.6. 
 1.28 “Series A Preferred Stock” means shares of the Company’s Series A Preferred
Stock, par value $0.001 per share. 
 1.29 “Series A-1 Preferred Stock” means shares
of the Company’s Series A-1 Preferred Stock, par value $0.001 per share. 
 1.30 “Series
A-2 Preferred Stock” means shares of the Company’s Series A-2 Preferred Stock, par value $0.001 per share. 

1.31 “Series A-3 Preferred Stock” means shares of the Company’s Series A-3 Preferred Stock, par value $0.001 per share. 
 1.32 “Series B Preferred Stock” means
shares of the Company’s Series B Preferred Stock, par value $0.001 per share. 
 1.33 “Series C Preferred Stock” means
shares of the Company’s Series C Preferred Stock, par value $0.001 per share. 
 2. Registration Rights. The Company covenants
and agrees as follows: 
 2.1 Demand Registration. 

(a) Form S-1 Demand. If at any time after the earlier of (i) five (5) years after the
date of this Agreement or (ii) one hundred eighty (180) days after the effective date of the registration statement for the IPO, the Company receives a request from Holders of a majority of the Registrable Securities then outstanding that
the Company file a Form S-1 registration statement for which the anticipated aggregate offering price would exceed $5,000,000, then the Company shall (i) within ten (10) days after the date such
request is given, give notice thereof (the “Demand Notice”) to all Holders other than the Initiating Holders; and (ii) as soon as practicable, and in any event within sixty (60) days after the date such request is given by
the Initiating Holders, file a Form S-1 registration statement under the Securities Act covering all Registrable Securities that the Initiating Holders requested to be registered and any additional Registrable
Securities requested to be included in such registration by any other Holders, as specified by notice given by each such Holder to the Company within twenty (20) days of the date the Demand Notice is given, and in each case, subject to the
limitations of Subsection 2.1(c) and Subsection 2.3. 
 (b) Form S-3 Demand. If
at any time when it is eligible to use a Form S-3 registration statement, the Company receives a request from Holders of at least thirty percent (30%) of the Registrable Securities then outstanding that the
Company file a Form S-3 registration statement with respect to outstanding Registrable Securities of such Holders having an anticipated 

  
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aggregate offering price of at least $5,000,000, then the Company shall (i) within ten (10) days after the date such request is given, give a Demand Notice to all Holders other than the
Initiating Holders; and (ii) as soon as practicable, and in any event within forty-five (45) days after the date such request is given by the Initiating Holders, file a Form S-3 registration
statement under the Securities Act covering all Registrable Securities requested to be included in such registration by any other Holders, as specified by notice given by each such Holder to the Company within twenty (20) days of the date the
Demand Notice is given, and in each case, subject to the limitations of Subsection 2.1(c) and Subsection 2.3. 
 (c)
Notwithstanding the foregoing obligations, if the Company furnishes to Holders requesting a registration pursuant to this Subsection 2.1 a certificate signed by the Company’s chief executive officer stating that in the good faith
judgment of the Company’s Board of Directors it would be materially detrimental to the Company and its stockholders for such registration statement to either become effective or remain effective for as long as such registration statement
otherwise would be required to remain effective, because such action would (i) materially interfere with a significant acquisition, corporate reorganization, or other similar transaction involving the Company; (ii) require premature
disclosure of material information that the Company has a bona fide business purpose for preserving as confidential; or (iii) render the Company unable to comply with requirements under the Securities Act or Exchange Act, then the Company shall
have the right to defer taking action with respect to such filing, and any time periods with respect to filing or effectiveness thereof shall be tolled correspondingly, for a period of not more than ninety (90) days after the request of the
Initiating Holders is given; provided, however, that the Company may not invoke this right more than once in any twelve (12) month period; and provided further that the Company shall not register any securities for
its own account or that of any other stockholder during such ninety (90) day period other than an Excluded Registration. 
 (d) The
Company shall not be obligated to effect, or to take any action to effect, any registration pursuant to Subsection 2.1(a)(i) during the period that is sixty (60) days before the Company’s good faith estimate of the date of filing
of, and ending on a date that is one hundred eighty (180) days after the effective date of, a Company-initiated registration, provided, that the Company is actively employing in good faith commercially reasonable efforts to cause such
registration statement to become effective; (ii) after the Company has effected two registrations pursuant to Subsection 2.1(a); or (iii) if the Initiating Holders propose to dispose of shares of Registrable Securities that may be
immediately registered on Form S-3 pursuant to a request made pursuant to Subsection 2.1(b). The Company shall not be obligated to effect, or to take any action to effect, any registration pursuant to
Subsection 2.1(b) (i) during the period that is thirty (30) days before the Company’s good faith estimate of the date of filing of, and ending on a date that is ninety (90) days after the effective date of, a
Company-initiated registration, provided, that the Company is actively employing in good faith commercially reasonable efforts to cause such registration statement to become effective; or (ii) if the Company has effected two registrations
pursuant to Subsection 2.1(b) within the twelve (12) month period immediately preceding the date of such request. A registration shall not be counted as “effected” for purposes of this Subsection 2.1(d) until such time
as the applicable registration statement has been declared effective by the SEC, unless the Initiating Holders withdraw their request for such registration, elect not to pay the registration expenses therefor, and forfeit their right to one demand
registration statement pursuant to Subsection 2.6, in which case such withdrawn registration statement shall be counted as “effected” for purposes of this Subsection 2.1(d). 

  
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 2.2 Company Registration. If the Company proposes to register (including, for this
purpose, a registration effected by the Company for stockholders other than the Holders) any of its securities under the Securities Act in connection with the public offering of such securities solely for cash (other than in an Excluded Registration
or the IPO), the Company shall, at such time, promptly give each Holder notice of such registration. Upon the request of each Holder given within twenty (20) days after such notice is given by the Company, the Company shall, subject to the
provisions of Subsection 2.3, cause to be registered all of the Registrable Securities that each such Holder has requested to be included in such registration. The Company shall have the right to terminate or withdraw any registration
initiated by it under this Subsection 2.2 before the effective date of such registration, whether or not any Holder has elected to include Registrable Securities in such registration. The expenses (other than Selling Expenses) of such
withdrawn registration shall be borne by the Company in accordance with Subsection 2.6. 
 2.3 Underwriting Requirements. 

(a) If, pursuant to Subsection 2.1, the Initiating Holders intend to distribute the Registrable Securities covered by their request by
means of an underwriting, they shall so advise the Company as a part of their request made pursuant to Subsection 2.1, and the Company shall include such information in the Demand Notice. The underwriter(s) will be selected by a majority in
interest of the Initiating Holders, subject only to the reasonable approval of the Company. In such event, the right of any Holder to include such Holder’s Registrable Securities in such registration shall be conditioned upon such Holder’s
participation in such underwriting and the inclusion of such Holder’s Registrable Securities in the underwriting to the extent provided herein. All Holders proposing to distribute their securities through such underwriting shall (together with
the Company as provided in Subsection 2.4(e)) enter into an underwriting agreement in customary form with the underwriter(s) selected for such underwriting. Notwithstanding any other provision of this Subsection 2.3, if the managing
underwriter(s) advise(s) the Initiating Holders in writing that marketing factors require a limitation on the number of shares to be underwritten, then the Initiating Holders shall so advise all Holders of Registrable Securities that otherwise would
be underwritten pursuant hereto, and the number of Registrable Securities that may be included in the underwriting shall be allocated among such Holders of Registrable Securities, including the Initiating Holders, in proportion (as nearly as
practicable) to the number of Registrable Securities owned by each Holder or in such other proportion as shall mutually be agreed to by all such selling Holders; provided, however, that the number of Registrable Securities held by the
Holders to be included in such underwriting shall not be reduced unless all other securities are first entirely excluded from the underwriting. To facilitate the allocation of shares in accordance with the above provisions, the Company or the
underwriters may round the number of shares allocated to any Holder to the nearest one hundred (100) shares. 
 (b) In connection with
any offering involving an underwriting of shares of the Company’s capital stock pursuant to Subsection 2.2, the Company shall not be required to include any of the Holders’ Registrable Securities in such underwriting unless the
Holders accept the terms of the underwriting as agreed upon between the Company and its underwriters, and then only in such quantity as the underwriters in their sole discretion determine will not jeopardize the success of the offering by the
Company. If the total number of securities, including Registrable Securities, requested by stockholders to be included in such offering exceeds the number of securities to be sold (other than by the Company) that the underwriters in their reasonable


  
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discretion determine is compatible with the success of the offering, then the Company shall be required to include in the offering only that number of such securities, including Registrable
Securities, which the underwriters and the Company in their sole discretion determine will not jeopardize the success of the offering. If the underwriters determine that less than all of the Registrable Securities requested to be registered can be
included in such offering, then the Registrable Securities that are included in such offering shall be allocated among the selling Holders in proportion (as nearly as practicable to) the number of Registrable Securities owned by each selling Holder
or in such other proportions as shall mutually be agreed to by all such selling Holders. To facilitate the allocation of shares in accordance with the above provisions, the Company or the underwriters may round the number of shares allocated to any
Holder to the nearest 100 shares. Notwithstanding the foregoing, in no event shall (i) the number of Registrable Securities included in the offering be reduced unless all other securities (other than securities to be sold by the Company) are
first entirely excluded from the offering, or (ii) the number of Registrable Securities included in the offering be reduced below thirty percent (30%) of the total number of securities included in such offering, unless such offering is the IPO,
in which case the selling Holders may be excluded further if the underwriters make the determination described above and no other stockholder’s securities are included in such offering. For purposes of the provision in this Subsection
2.3(b) concerning apportionment, for any selling Holder that is a partnership, limited liability company, or corporation, the partners, members, retired partners, retired members, stockholders, and Affiliates of such Holder, or the estates and
Immediate Family Members of any such partners, retired partners, members, and retired members and any trusts for the benefit of any of the foregoing Persons, shall be deemed to be a single “selling Holder,” and any pro rata reduction with
respect to such “selling Holder” shall be based upon the aggregate number of Registrable Securities owned by all Persons included in such “selling Holder,” as defined in this sentence. 

(c) For purposes of Subsection 2.1, a registration shall not be counted as “effected” if, as a result of an exercise of the
underwriter’s cutback provisions in Subsection 2.3(a), fewer than fifty percent (50%) of the total number of Registrable Securities that Holders have requested to be included in such registration statement are actually included. 

2.4 Obligations of the Company. Whenever required under this Section 2 to effect the registration of any
Registrable Securities, the Company shall, as expeditiously as reasonably possible: 
 (a) prepare and file with the SEC a registration
statement with respect to such Registrable Securities and use its commercially reasonable efforts to cause such registration statement to become effective and, upon the request of the Holders of a majority of the Registrable Securities registered
thereunder, keep such registration statement effective for a period of up to one hundred twenty (120) days or, if earlier, until the distribution contemplated in the registration statement has been completed; provided, however,
that (i) such one hundred twenty (120) day period shall be extended for a period of time equal to the period the Holder refrains, at the request of an underwriter of Common Stock (or other securities) of the Company, from selling any
securities included in such registration, and (ii) in the case of any registration of Registrable Securities on Form S-3 that are intended to be offered on a continuous or delayed basis, subject to
compliance with applicable SEC rules, such one hundred twenty (120) day period shall be extended, if necessary, to keep the registration statement effective until all such Registrable Securities are sold; 

  
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 (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 Securities Act in order to enable the disposition of all securities covered by such registration statement; 

(c) furnish to the selling Holders such numbers of copies of a prospectus, including a preliminary prospectus, as required by the Securities
Act, and such other documents as the Holders may reasonably request in order to facilitate their disposition of their Registrable Securities; 

(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 shall be reasonably requested by the selling Holders; provided that the Company shall not be required 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; 

(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 underwriter(s) of such offering; 
 (f) use its commercially reasonable efforts to cause all such Registrable
Securities covered by such registration statement to be listed on a national securities exchange or trading system and each securities exchange and trading system (if any) on which similar securities issued by the Company are then listed; 

(g) provide a transfer agent and registrar for all Registrable Securities registered pursuant to this Agreement and provide a CUSIP number for
all such Registrable Securities, in each case not later than the effective date of such registration; 
 (h) promptly make available for
inspection by the selling Holders, any managing underwriter(s) participating in any disposition pursuant to such registration statement, and any attorney or accountant or other agent retained by any such underwriter or selected by the selling
Holders, all financial and other records, pertinent corporate documents, and properties of the Company, and cause the Company’s officers, directors, employees, and independent accountants to supply all information reasonably requested by any
such seller, underwriter, attorney, accountant, or agent, in each case, as necessary or advisable to verify the accuracy of the information in such registration statement and to conduct appropriate due diligence in connection therewith; 

(i) notify each selling Holder, promptly after the Company receives notice thereof, of the time when such registration statement has been
declared effective or a supplement to any prospectus forming a part of such registration statement has been filed; and 

  
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 (j) after such registration statement becomes effective, notify each selling Holder of any
request by the SEC that the Company amend or supplement such registration statement or prospectus. 
 In addition, the Company shall ensure
that, at all times after any registration statement covering a public offering of securities of the Company under the Securities Act shall have become effective, its insider trading policy shall provide that the Company’s directors may
implement a trading program under Rule 10b5-1 of the Exchange Act. 
 2.5 Furnish Information.
It shall be a condition precedent to the obligations of the Company to take any action pursuant to this Section 2 with respect to the Registrable Securities of any selling Holder that such Holder shall furnish to the
Company such information regarding itself, the Registrable Securities held by it, and the intended method of disposition of such securities as is reasonably required to effect the registration of such Holder’s Registrable Securities. 

2.6 Expenses of Registration. All expenses (other than Selling Expenses) incurred in connection with registrations, filings or
qualifications pursuant to Section 2, including all registration, filing, and qualification fees; printers’ and accounting fees; fees and disbursements of counsel for the Company; and the reasonable fees and
disbursements of one counsel for the selling Holders selected by the Holders of a majority of the Registrable Securities to be registered (“Selling Holder Counsel”), shall be borne and paid by the Company; provided,
however, that the Company shall not be required to pay for any expenses of any registration proceeding begun pursuant to Subsection 2.1 if the registration request is subsequently withdrawn at the request of the Holders of a majority
of the Registrable Securities to be registered (in which case all selling Holders shall bear such expenses pro rata based upon the number of Registrable Securities that were to be included in the withdrawn registration), unless the Holders of a
majority of the Registrable Securities agree to forfeit their right to one registration pursuant to Subsection 2.1(a) or Subsection 2.1(b), as the case may be; provided further that if, at the time of such withdrawal, the
Holders shall have learned of a material adverse change in the condition, business, or prospects of the Company from that known to the Holders at the time of their request and have withdrawn the request with reasonable promptness after learning of
such information then the Holders shall not be required to pay any of such expenses and shall not forfeit their right to one registration pursuant to Subsection 2.1(a) or Subsection 2.1(b). All Selling Expenses relating to Registrable
Securities registered pursuant to this Section 2 shall be borne and paid by the Holders pro rata on the basis of the number of Registrable Securities registered on their behalf. 

2.7 Delay of Registration. No Holder shall have any right to obtain or seek an injunction restraining or otherwise delaying any
registration pursuant to this Agreement as the result of any controversy that might arise with respect to the interpretation or implementation of this Section 2. 

2.8 Indemnification. If any Registrable Securities are included in a registration statement under this
Section 2: 

  
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 (a) To the extent permitted by law, the Company will indemnify and hold harmless each selling
Holder and the partners, members, officers, directors and stockholders of each such Holder; legal counsel and accountants for each such Holder; any underwriter (as defined in the Securities Act) for each such Holder; and each Person, if any, who
controls such Holder or underwriter within the meaning of the Securities Act or the Exchange Act, against any Damages, and the Company will pay to each such Holder, underwriter, controlling Person or other aforementioned Person any legal or other
expenses reasonably incurred thereby in connection with investigating or defending any claim or proceeding from which Damages may result, as such expenses are incurred; provided, however, that the indemnity agreement contained in this
Subsection 2.8(a) shall not apply to amounts paid in settlement of any such claim or proceeding if such settlement is effected without the consent of the Company, which consent shall not be unreasonably withheld, nor shall the Company be
liable for any Damages to the extent that they arise out of or are based upon actions or omissions made in reliance upon and in conformity with written information furnished by or on behalf of any such Holder, underwriter, controlling Person or
other aforementioned Person expressly for use in connection with such registration. 
 (b) To the extent permitted by law, each selling
Holder, severally and not jointly, will indemnify and hold harmless the Company, and each of its directors, each of its officers who has signed the registration statement, each Person (if any), who controls the Company within the meaning of the
Securities Act, legal counsel and accountants for the Company, any underwriter (as defined in the Securities Act), any other Holder selling securities in such registration statement and any controlling Person of any such underwriter or other Holder,
against any Damages, in each case only to the extent that such Damages arise out of or are based upon actions or omissions made in reliance upon and in conformity with written information furnished by or on behalf of such selling Holder expressly
for use in connection with such registration; and each such selling Holder will pay to the Company and each other aforementioned Person any legal or other expenses reasonably incurred thereby in connection with investigating or defending any claim
or proceeding from which Damages may result, as such expenses are incurred; provided, however, that the indemnity agreement contained in this Subsection 2.8(b) shall not apply to amounts paid in settlement of any such claim or
proceeding if such settlement is effected without the consent of the Holder, which consent shall not be unreasonably withheld; and provided further that in no event shall the aggregate amounts payable by any Holder by way of indemnity
or contribution under Subsections 2.8(b) and 2.8(d) exceed the proceeds from the offering received by such Holder (net of any Selling Expenses paid by such Holder), except in the case of fraud or willful misconduct by such Holder. 

(c) Promptly after receipt by an indemnified party under this Subsection 2.8 of notice of the commencement of any action (including any
governmental action) for which a party may be entitled to indemnification hereunder, such indemnified party will, if a claim in respect thereof is to be made against any indemnifying party under this Subsection 2.8, give the indemnifying
party notice of the commencement thereof. The indemnifying party shall have the right to participate in such action and, to the extent the indemnifying party so desires, participate jointly with any other indemnifying party to which notice has been
given, and to assume the defense thereof with counsel mutually satisfactory to the parties; provided, however, that an indemnified party (together with all other indemnified parties that may be represented without conflict by one
counsel) shall have the right to retain one separate counsel, with the fees and expenses 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 

  
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in such action. The failure to give notice to the indemnifying party within a reasonable time of the commencement of any such action shall relieve such indemnifying party of any liability to the
indemnified party under this Subsection 2.8, to the extent that such failure materially prejudices the indemnifying party’s ability to defend such action. The failure to give notice to the indemnifying party will not relieve it of any
liability that it may have to any indemnified party otherwise than under this Subsection 2.8. 
 (d) To provide
for just and equitable contribution to joint liability under the Securities Act in any case in which either (i) any party otherwise entitled to indemnification hereunder makes a claim for indemnification pursuant to this Subsection 2.8
but it is judicially determined (by the entry of a final judgment or decree by a court of competent jurisdiction and the expiration of time to appeal or the denial of the last right of appeal) that such indemnification may not be enforced in such
case, notwithstanding the fact that this Subsection 2.8 provides for indemnification in such case, or (ii) contribution under the Securities Act may be required on the part of any party hereto for which indemnification
is provided under this Subsection 2.8, then, and in each such case, such parties will contribute to the aggregate losses, claims, damages, liabilities or expenses to which they may be subject (after contribution from others) in such
proportion as is appropriate to reflect the relative fault of each of the indemnifying party and the indemnified party in connection with the statements, omissions, or other actions that resulted in such loss, claim, damage, liability or expense, as
well as to reflect any other relevant equitable considerations. The relative fault of the indemnifying party and of the indemnified party shall be determined by reference to, among other things, whether the untrue or allegedly untrue statement of a
material fact, or the omission or alleged omission of 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, however, that, in any such case, (x) no Holder will be required to contribute any amount in excess of the public offering price of all such Registrable Securities offered
and sold by such Holder pursuant to such registration statement, and (y) no Person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) will be entitled to contribution from any Person who was
not guilty of such fraudulent misrepresentation; and provided further that in no event shall a Holder’s liability pursuant to this Subsection 2.8(d), when combined with the amounts paid or payable by such Holder pursuant to
Subsection 2.8(b), exceed the proceeds from the offering received by such Holder (net of any Selling Expenses paid by such Holder), except in the case of willful misconduct or fraud by such Holder. 

(e) Notwithstanding the foregoing, to the extent that the provisions on indemnification and contribution contained in the underwriting
agreement entered into in connection with the underwritten public offering are in conflict with the foregoing provisions, the provisions in the underwriting agreement shall control. 

(f) Unless otherwise superseded by an underwriting agreement entered into in connection with the underwritten public offering, the obligations
of the Company and Holders under this Subsection 2.8 shall survive the completion of any offering of Registrable Securities in a registration under this Section 2, and otherwise shall survive the termination of this
Agreement. 

  
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 2.9 Reports Under Exchange Act. With a view to making available to the Holders the
benefits of SEC Rule 144 and any other rule or regulation of the SEC that may at any time permit a Holder to sell securities of the Company to the public without registration or pursuant to a registration on Form
S-3, the Company shall: 
 (a) make and keep available adequate current public information, as those
terms are understood and defined in SEC Rule 144, at all times after the effective date of the registration statement filed by the Company for the IPO; 

(b) use commercially reasonable efforts to file with the SEC in a timely manner all reports and other documents required of the Company under
the Securities Act and the Exchange Act (at any time after the Company has become subject to such reporting requirements); and 
 (c)
furnish to any Holder, so long as the Holder owns any Registrable Securities, forthwith upon request (i) to the extent accurate, a written statement by the Company that it has complied with the reporting requirements of SEC Rule 144 (at any
time after ninety (90) days after the effective date of the registration statement filed by the Company for the IPO), the Securities Act and the Exchange Act (at any time after the Company has become subject to such reporting requirements), or
that it qualifies as a registrant whose securities may be resold pursuant to Form S 3 (at any time after the Company so qualifies); (ii) a copy of the most recent annual or quarterly report of the Company and such other reports and documents so
filed by the Company; and (iii) such other information as may be reasonably requested in availing any Holder of any rule or regulation of the SEC that permits the selling of any such securities without registration (at any time after the
Company has become subject to the reporting requirements under the Exchange Act) or pursuant to Form S-3 (at any time after the Company so qualifies to use such form). 

2.10 Limitations on Subsequent Registration Rights. From and after the date of this Agreement, the Company shall not, without the prior
written consent of the Holders of at least fifty percent (50%) of the Registrable Securities then outstanding, enter into any agreement with any holder or prospective holder of any securities of the Company that (i) would provide to such holder
the right to include securities in any registration on other than a subordinate basis after all Holders have had the opportunity to include in the registration and offering all shares of Registrable Securities that they wish to so include or
(ii) allow such holder or prospective holder to initiate a demand for registration of any securities held by such holder or prospective holder; provided that this limitation shall not apply to any additional Investor who becomes a party to this
Agreement in accordance with Subsection 6.9. 
 2.11 “Market Stand off” Agreement. Each Holder hereby
agrees that it will not, without the prior written consent of the managing underwriter, during the period commencing on the date of the final prospectus relating to the IPO and ending on the date specified by the Company and the managing underwriter
(such period not to exceed one hundred eighty (180) days plus such additional period up to eighteen (18) additional days as may be requested by the Company or an underwriter to accommodate regulatory restrictions on (1) the
publication or other distribution of research reports and (2) analyst recommendations and opinions, including, but not limited to, the restrictions contained in FINRA Rule 2711(f)(4) or NYSE Rule 472(f)(4), or any successor provisions or
amendments thereto), (i) lend; offer; pledge; sell; contract to sell; sell any option or 

  
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contract to purchase; purchase any option or contract to sell; grant any option, right, or warrant to purchase; or otherwise transfer or dispose of, directly or indirectly, any shares of Common
Stock or any securities convertible into or exercisable or exchangeable (directly or indirectly) for Common Stock held immediately before the effective date of the registration statement for such offering or (ii) enter into any swap or other
arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of such securities, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Common Stock or
other securities, in cash, or otherwise. The foregoing provisions of this Subsection 2.11 shall apply only to the IPO, shall not apply to the sale of any shares to an underwriter pursuant to an underwriting agreement for such IPO and shall be
applicable to the Holders only if all officers and directors of the Company and holders of at least five percent (5%) of the outstanding Common Stock (after giving effect to conversion into Common Stock of all outstanding shares of Preferred
Stock) are subject to the same restrictions. The underwriters in connection with such registration are intended third party beneficiaries of this Subsection 2.11 and shall have the right, power and authority to enforce the provisions hereof
as though they were a party hereto. Each Holder further agrees to execute such agreements as may be reasonably requested by the underwriters in connection with such registration that are consistent with this Subsection 2.11 or that are
necessary to give further effect thereto. 
 2.12 Restrictions on Transfer. 

(a) The Preferred Stock and the Registrable Securities shall not be sold, pledged, or otherwise transferred in violation of this Agreement,
and the Company shall not recognize and shall issue stop-transfer instructions to its transfer agent with respect to any such sale, pledge, or transfer, except upon the conditions specified in this Agreement, which conditions are intended to ensure
compliance with the provisions of the Securities Act. A transferring Holder will cause any proposed purchaser, pledgee, or transferee of the Preferred Stock and the Registrable Securities held by such Holder to agree to take and hold such securities
subject to the provisions and upon the conditions specified in this Agreement. 
 (b) Each certificate, instrument or book entry
representing (i) the Preferred Stock, (ii) the Registrable Securities, and (iii) any other securities issued in respect of the securities referenced in clauses (i) and (ii), upon any stock split, stock dividend, recapitalization,
merger, consolidation, or similar event, shall (unless otherwise permitted by the provisions of Subsection 2.12(c)) be notated with a legend substantially in the following form: 

THE SECURITIES REPRESENTED HEREBY HAVE BEEN ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
1933, AS AMENDED. SUCH SHARES MAY NOT BE SOLD, PLEDGED, OR TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR A VALID EXEMPTION FROM THE REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF SAID ACT. 

THE SECURITIES REPRESENTED HEREBY MAY BE TRANSFERRED ONLY IN ACCORDANCE WITH THE TERMS OF AN AGREEMENT BETWEEN THE COMPANY AND
THE STOCKHOLDER, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF THE COMPANY. 

  
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 The Holders consent to the Company making a notation in its records and giving instructions to
any transfer agent of the Restricted Securities in order to implement the restrictions on transfer set forth in this Subsection 2.12. 

(c) The holder of such Restricted Securities, by acceptance thereof, agrees to comply in all respects with the provisions of this
Section 2. Before any proposed sale, pledge or transfer of any Restricted Securities, unless there is in effect a registration statement under the Securities Act covering the proposed transaction, the Holder thereof shall
give notice to the Company of such Holder’s intention to effect such sale, pledge or transfer. Each such notice shall describe the manner and circumstances of the proposed sale, pledge or transfer in sufficient detail and, if reasonably
requested by the Company, shall be accompanied at such Holder’s expense by either (i) a written opinion of legal counsel who shall, and whose legal opinion shall, be reasonably satisfactory to the Company, addressed to the Company, to the
effect that the proposed transaction may be effected without registration under the Securities Act; (ii) a “no action” letter from the SEC to the effect that the proposed sale, pledge or transfer of such Restricted Securities without
registration will not result in a recommendation by the staff of the SEC that action be taken with respect thereto; or (iii) any other evidence reasonably satisfactory to counsel to the Company to the effect that the proposed sale, pledge or
transfer of the Restricted Securities may be effected without registration under the Securities Act, whereupon the Holder of such Restricted Securities shall be entitled to sell, pledge or transfer such Restricted Securities in accordance with the
terms of the notice given by the Holder to the Company. The Company will not require such a legal opinion or “no action” letter (x) in any transaction in compliance with SEC Rule 144 or (y) in any transaction in which such Holder
distributes Restricted Securities to an Affiliate of such Holder for no consideration; provided that each transferee agrees in writing to be subject to the terms of this Subsection 2.12. Each certificate, instrument or book
entry representing the Restricted Securities transferred as above provided shall be notated with, except if such transfer is made pursuant to SEC Rule 144, the appropriate restrictive legend set forth in Subsection 2.12(b), except that such
certificate, instrument or book entry shall not be notated with such restrictive legend if, in the opinion of counsel for such Holder and the Company, such legend is not required in order to establish compliance with any provisions of the Securities
Act. 
 2.13 Termination of Registration Rights. The right of any Holder to request registration or inclusion of Registrable
Securities in any registration pursuant to Subsection 2.1 or Subsection 2.2 shall terminate upon the earliest to occur of: 

(a) immediately before the closing of a Deemed Liquidation Event, as such term is defined in the Company’s Certificate of Incorporation;

 (b) such time after the IPO as SEC Rule 144 or another similar exemption under the Securities Act is available for the sale of all of
such Holder’s shares without limitation during a three-month period without registration; and 
 (c) the seventh (7th) anniversary of the IPO. 

  
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 3. Information and Observer Rights. 

3.1 Delivery of Financial Statements. The Company shall deliver to each Major Investor, provided that the Board of
Directors has not reasonably determined that such Major Investor is (or, in the case of a Major Investor that is an individual, is employed by or serves as a consultant to) a competitor of the Company: 

(a) as soon as practicable, but in any event within one hundred twenty (120) days after the end of each fiscal year of the Company,
(i) a balance sheet as of the end of such year, (ii) statements of income and of cash flows for such year, and a comparison between (x) the actual amounts as of and for such fiscal year and (y) the comparable amounts for the
prior year and as included in the Budget (as defined in Subsection 3.1(e)) for such year, with an explanation of any material differences between such amounts and a schedule as to the sources and applications of funds for such year, and
(iii) a statement of stockholders’ equity as of the end of such year, all such financial statements audited and certified by independent public accountants selected by the Company and approved by the Board of Directors, including the
Preferred Directors; 
 (b) as soon as practicable, but in any event within forty-five (45) days after the end of each of the first
three (3) quarters of each fiscal year of the Company, unaudited statements of income and of cash flows for such fiscal quarter, and an unaudited balance sheet and a statement of stockholders’ equity as of the end of such fiscal quarter,
all prepared in accordance with GAAP (except that such financial statements may (i) be subject to normal year-end audit adjustments and (ii) not contain all notes thereto that may be required in
accordance with GAAP); 
 (c) as soon as practicable, but in any event within forty-five (45) days after the end of each of the first
three (3) quarters of each fiscal year of the Company, a statement showing the number of shares of each class and series of capital stock and securities convertible into or exercisable for shares of capital stock outstanding at the end of the
period, the Common Stock issuable upon conversion or exercise of any outstanding securities convertible or exercisable for Common Stock and the exchange ratio or exercise price applicable thereto, and the number of shares of issued stock options and
stock options not yet issued but reserved for issuance, if any, all in sufficient detail as to permit any Major Investor to calculate its percentage equity ownership in the Company, and certified by the chief financial officer or chief executive
officer of the Company as being true, complete and correct; 
 (d) as soon as practicable, but in any event thirty (30) days before the
end of each fiscal year, a budget and business plan for the next fiscal year (collectively, the “Budget”), approved by the Board of Directors and prepared on a quarterly basis, including balance sheets, income statements, and
statements of cash flow for such quarters and, promptly after prepared, any other budgets or revised budgets prepared by the Company; and 

(e) such other information relating to the financial condition, business, prospects or corporate affairs of the Company as any Major Investor
may from time to time reasonably request; provided, however, that the Company shall not be obligated under this Subsection 3.1 to provide information (i) that the Company reasonably determines in good faith to be a trade
secret or confidential information (unless covered by an enforceable confidentiality agreement, in form acceptable to the Company) or (ii) the disclosure of which would adversely affect the attorney-client privilege between the Company and its
counsel. 

  
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 If, for any period, the Company has any subsidiary whose accounts are consolidated with those of
the Company, then in respect of such period the financial statements delivered pursuant to the foregoing sections shall be the consolidated and consolidating financial statements of the Company and all such consolidated subsidiaries. 

Notwithstanding anything else in this Subsection 3.1 to the contrary, the Company may cease providing the information set forth in this
Subsection 3.1 during the period starting with the date sixty (60) days before the Company’s good-faith estimate of the date of filing of a registration statement if it reasonably concludes it must do so to comply with the SEC rules
applicable to such registration statement and related offering; provided that the Company’s covenants under this Subsection 3.1 shall be reinstated at such time as the Company is no longer actively employing its
commercially reasonable efforts to cause such registration statement to become effective. 
 3.2 Inspection. The Company shall permit
each Major Investor (provided that the Board of Directors has not reasonably determined that such Major Investor is, or, in the case of a Major Investor that is an individual, is employed by or serves as a consultant to, a competitor of the
Company), at such Major Investor’s expense, to visit and inspect the Company’s properties; examine its books of account and records; and discuss the Company’s affairs, finances, and accounts with its officers, during normal business
hours of the Company as may be reasonably requested by the Major Investor; provided, however, that the Company shall not be obligated pursuant to this Subsection 3.2 to provide access to any information that it reasonably and in
good faith considers to be a trade secret or confidential information (unless covered by an enforceable confidentiality agreement, in form acceptable to the Company) or the disclosure of which would adversely affect the attorney-client privilege
between the Company and its counsel. 
 3.3 Termination of Information Rights. The covenants set forth in Subsection 3.1 and
Subsection 3.2 shall terminate and be of no further force or effect (i) immediately before the consummation of the IPO, (ii) when the Company first becomes subject to the periodic reporting requirements of Section 12(g) or
15(d) of the Exchange Act, or (iii) immediately before a Deemed Liquidation Event, as such term is defined in the Company’s Certificate of Incorporation, whichever event occurs first. 

3.4 Confidentiality. Each Investor agrees that such Investor will keep confidential and will not disclose, divulge or use for any
purpose (other than to monitor its investment in the Company) any confidential information obtained from the Company pursuant to the terms of this Agreement (including notice of the Company’s intention to file a registration statement), unless
such confidential information (a) is known or becomes known to the public in general (other than as a result of a breach of this Subsection 3.4 by such Investor), (b) is or has been independently developed or conceived by any
Investor without use of the Company’s confidential information, or (c) is or has been made known or disclosed to any Investor by a third party without a breach of any obligation of confidentiality such third party may have to the Company;
provided, however, that an Investor may disclose confidential information (i) to its attorneys, accountants, consultants, and other professionals to the extent necessary to obtain their services in connection with monitoring its
investment in the Company; (ii) to any prospective 

  
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purchaser of any Registrable Securities from such Investor, if such prospective purchaser agrees to be bound by the provisions of this Subsection 3.4; (iii) to any existing or
prospective Affiliate, partner, member, stockholder or wholly owned subsidiary of such Investor in the ordinary course of business, provided that such Investor informs such Person that such information is confidential and directs such
Person to maintain the confidentiality of such information; or (iv) as may otherwise be required by law, provided that such Investor promptly notifies the Company of such disclosure and takes reasonable steps to minimize the
extent of any such required disclosure. 
 4. Rights to Future Stock Issuances. 

4.1 Right of First Offer. Subject to the terms and conditions of this Subsection 4.1 and applicable securities laws, if the
Company proposes to offer or sell any New Securities, the Company shall first offer such New Securities to each Major Investor. A Major Investor shall be entitled to apportion the right of first offer hereby granted to it among itself and its
Affiliates in such proportions as it deems appropriate. 
 (a) The Company shall give notice (the “Offer Notice”) to each
Major Investor, stating (i) its bona fide intention to offer such New Securities, (ii) the number of such New Securities to be offered, and (iii) the price and terms, if any, upon which it proposes to offer such New Securities. 

(b) By notification to the Company within twenty (20) days after the Offer Notice is given, each Major Investor may elect to purchase or
otherwise acquire, at the price and on the terms specified in the Offer Notice, up to that portion of such New Securities which equals the proportion that the Common Stock then held, or issuable (directly or indirectly) upon conversion and/or
exercise, as applicable, of the Preferred Stock and any other Derivative Securities then held, by such Major Investor bears to the total Common Stock of the Company then outstanding (assuming full conversion and/or exercise, as applicable, of all
Preferred Stock and other Derivative Securities). At the expiration of such twenty (20) day period, the Company shall promptly notify each Major Investor that elects to purchase or acquire all the shares available to it (each, a “Fully
Exercising Investor”) of any other Major Investor’s failure to do likewise. During the ten (10) day period commencing after the Company has given such notice, each Fully Exercising Investor may, by giving notice to the Company,
elect to purchase or acquire, in addition to the number of shares specified above, up to that portion of the New Securities for which Major Investors were entitled to subscribe but that were not subscribed for by the Major Investors which is equal
to the proportion that the Common Stock issued and held, or issuable (directly or indirectly) upon conversion and/or exercise, as applicable, of Preferred Stock and any other Derivative Securities then held, by such Fully Exercising Investor bears
to the Common Stock issued and held, or issuable (directly or indirectly) upon conversion and/or exercise, as applicable, of the Preferred Stock and any other Derivative Securities then held, by all Fully Exercising Investors who wish to purchase
such unsubscribed shares. The closing of any sale pursuant to this Subsection 4.1(b) shall occur within the later of ninety (90) days of the date that the Offer Notice is given and the date of initial sale of New Securities pursuant to
Subsection 4.1(c). 

  
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 (c) If all New Securities referred to in the Offer Notice are not elected to be purchased or
acquired as provided in Subsection 4.1(b), the Company may, during the ninety (90) day period following the expiration of the periods provided in Subsection 4.1(b), offer and sell the remaining unsubscribed portion of such New
Securities to any Person or Persons at a price not less than, and upon terms no more favorable to the offeree than, those specified in the Offer Notice. If the Company does not enter into an agreement for the sale of the New Securities within such
period, or if such agreement is not consummated within thirty (30) days of the execution thereof, the right provided hereunder shall be deemed to be revived and such New Securities shall not be offered unless first reoffered to the Major
Investors in accordance with this Subsection 4.1. 
 (d) The right of first offer in this Subsection 4.1 shall not be
applicable to (i) Exempted Securities (as defined in the Company’s Certificate of Incorporation) or (ii) shares of Series C Preferred Stock issued after the date hereof pursuant to the Purchase Agreement. 

4.2 Termination. The covenants set forth in Subsection 4.1 shall terminate and be of no further force or effect
(i) immediately before the consummation of the IPO, (ii) when the Company first becomes subject to the periodic reporting requirements of Section 12(g) or 15(d) of the Exchange Act, or (iii) immediately before a Deemed
Liquidation Event, as such term is defined in the Company’s Certificate of Incorporation, whichever event occurs first. 
 5.
Additional Covenants. 
 5.1 Insurance. The Company shall use its commercially reasonable efforts to maintain in effect, from
financially sound and reputable insurers, Directors and Officers liability insurance and term “key person” insurance on the Chief Executive Officer, each in an amount and on terms and conditions satisfactory to the Board of Directors,
until such time as the Board of Directors determines that such insurance should be discontinued. The key person policy shall name the Company as loss payee, and neither policy shall be cancelable by the Company without prior approval by the Board of
Directors including the Preferred Directors. 
 5.2 Employee Agreements. The Company will cause (i) each person now or hereafter
employed by it or by any subsidiary (or engaged by the Company or any subsidiary as a consultant/independent contractor) with access to confidential information and/or trade secrets to enter into a nondisclosure and proprietary rights assignment
agreement and (ii) each Key Employee to enter into a one (1) year noncompetition and nonsolicitation agreement, each in a form acceptable to the Investors holding a majority of the Registrable Securities. In addition, the Company shall not
amend, modify, terminate, waive, or otherwise alter, in whole or in part, any of the above-referenced agreements, any noncompetition or nonsolicitation agreement or any restricted stock agreement between the Company and any employee, without the
consent of the Board of Directors, including at least one of the Preferred Directors. 
 5.3 Employee Stock. Unless otherwise approved
by the Board of Directors, including at least one of the Preferred Directors, all future employees and consultants of the Company who purchase, receive options to purchase, or receive awards of shares of the Company’s capital stock after the
date hereof shall be required to execute restricted stock or option agreements, as applicable, providing for (i) vesting of shares over a four (4) year period, with the first twenty-five percent (25%) of such shares vesting following
twelve (12) months of continued employment or service, and the remaining shares vesting in equal quarterly installments over the following thirty-six (36) months, and (ii) a market stand-off provision substantially similar to that 

  
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in Subsection 2.11. In addition, unless otherwise approved by the Board of Directors, including at least one of the Preferred Directors, the Company shall retain a “right of first
refusal” on employee transfers until the Company’s IPO and shall have the right to repurchase unvested shares at cost upon termination of employment of a holder of restricted stock. 

5.4 Qualified Small Business Stock. The Company shall use commercially reasonable efforts to cause the shares of Preferred Stock issued
on or prior to June 16, 2017 (the date of the last closing held under that certain Series B Preferred Stock Purchase Agreement, dated as of January 5, 2017, by and among the Company and the other parties thereto), as well as any shares
into which such shares are converted, within the meaning of Section 1202(f) of the Internal Revenue Code (the “Code”), to constitute “qualified small business stock” as defined in Section 1202(c) of the Code;
provided, however, that such requirement shall not be applicable if the Board of Directors of the Company determines, in its good-faith business judgment, that such qualification is inconsistent with the best interests of the Company.
The Company shall submit to its stockholders (including the Investors) and to the Internal Revenue Service any reports that may be required under Section 1202(d)(1)(C) of the Code and the regulations promulgated thereunder. In addition, within
twenty (20) business days after any Investor’s written request therefor, the Company shall, at its option, either (i) deliver to such Investor a written statement indicating whether (and what portion of) such Investor’s interest
in the Company constitutes “qualified small business stock” as defined in Section 1202(c) of the Code or (ii) deliver to such Investor such factual information in the Company’s possession as is reasonably necessary to enable
such Investor to determine whether (and what portion of) such Investor’s interest in the Company constitutes “qualified small business stock” as defined in Section 1202(c) of the Code. 

5.5 Matters Requiring Investor Director Approval. So long as the holders of Preferred Stock are entitled to elect a Preferred Director,
the Company hereby covenants and agrees with the Investors that it shall not, nor shall it permit any subsidiary to, without approval of the Board of Directors, which approval must include the affirmative vote of at least one of the Preferred
Directors: 
 (a) make any loan or advance to, or own any stock or other securities of, any subsidiary or other corporation, partnership, or
other entity unless it is wholly owned by the Company; 
 (b) make any loan or advance to any Person, including, without limitation, any
employee or director of the Company or any subsidiary, except advances and similar expenditures in the ordinary course of business or under the terms of an employee stock or option plan approved by the Board of Directors, including at least one of
the Preferred Directors; 
 (c) guarantee, directly or indirectly, any indebtedness except for trade accounts of the Company or any
subsidiary arising in the ordinary course of business; 
 (d) make any investment inconsistent with any investment policy approved by the
Board of Directors; 

  
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 (e) incur any aggregate indebtedness in excess of $250,000 that is not already included in a
budget approved by the Board of Directors, other than trade credit incurred in the ordinary course of business; 
 (f) otherwise enter into
or be a party to any transaction with any director, officer, or employee of the Company or any “associate” (as defined in Rule 12b-2 promulgated under the Exchange Act) of any such Person, except for
transactions contemplated by this Agreement and the Purchase Agreement; transactions resulting in payments to or by the Company in an aggregate amount less than $100,000 per year; or transactions made in the ordinary course of business and pursuant
to reasonable requirements of the Company’s business and upon fair and reasonable terms that are approved by a majority of the Board of Directors; 

(g) hire, terminate, or change the compensation of the executive officers, including approving any option grants or stock awards to executive
officers; 
 (h) change the principal business of the Company, enter new lines of business, or exit the current line of business; 

(i) sell, assign, license, pledge, or encumber material technology or intellectual property, other than licenses granted in the ordinary
course of business; 
 (j) increase the shares of Common Stock reserved for issuance under the Company’s 2015 Stock Incentive Plan or
adopt any other equity incentive plan; or 
 (k) enter into any corporate strategic relationship involving the payment, contribution, or
assignment by the Company or to the Company of money or assets greater than $250,000. 
 5.6 Board Matters. Unless otherwise
determined by the vote of a majority of the directors then in office, the Board of Directors shall meet at least quarterly in accordance with an agreed-upon schedule, unless agreed by a majority of the Board of Directors, including at least one of
the Preferred Directors. The Company shall reimburse the nonemployee directors for all reasonable out-of-pocket travel expenses incurred (consistent with the
Company’s travel policy) in connection with attending meetings of the Board of Directors. The Company shall cause to be established, as soon as practicable after such request, and will maintain, an audit and compensation committee, each of
which shall consist solely of non-management directors. Each non-employee director shall be entitled in such person’s discretion to be a member of any Board
committee. Each committee of the Board of Directors shall include at least one Preferred Director. 
 5.7 Successor Indemnification.
If the Company or any of its successors or assignees consolidates with or merges into any other Person and is not the continuing or surviving corporation or entity of such consolidation or merger, then to the extent necessary, proper provision shall
be made so that the successors and assignees of the Company assume the obligations of the Company with respect to indemnification of members of the Board of Directors as in effect immediately before such transaction, whether such obligations are
contained in the Company’s Bylaws, its Certificate of Incorporation, or elsewhere, as the case may be. 

  
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 5.8 Indemnification Matters. The Company hereby acknowledges that one (1) or more of
the directors nominated to serve on the Board of Directors by the Investors (each a “Fund Director”) may have certain rights to indemnification, advancement of expenses and/or insurance provided by one or more of the Investors and
certain of their affiliates (collectively, the “Fund Indemnitors”). The Company hereby agrees (i) that it is the indemnitor of first resort (i.e., its obligations to any such Fund Director are primary and any obligation of the
Fund Indemnitors to advance expenses or to provide indemnification for the same expenses or liabilities incurred by such Fund Director are secondary), (ii) that it shall be required to advance the full amount of expenses incurred by such Fund
Director and shall be liable for the full amount of all expenses, judgments, penalties, fines and amounts paid in settlement by or on behalf of any such Fund Director to the extent legally permitted and as required by the Company’s Certificate
of Incorporation or Bylaws of the Company (or any agreement between the Company and such Fund Director), without regard to any rights such Fund Director may have against the Fund Indemnitors, and, (iii) that it irrevocably waives, relinquishes
and releases the Fund Indemnitors from any and all claims against the Fund Indemnitors for contribution, subrogation or any other recovery of any kind in respect thereof. The Company further agrees that no advancement or payment by the Fund
Indemnitors on behalf of any such Fund Director with respect to any claim for which such Fund Director has sought indemnification from the Company shall affect the foregoing and the Fund Indemnitors shall have a right of contribution and/or be
subrogated to the extent of such advancement or payment to all of the rights of recovery of such Fund Director against the Company. 
 5.9
Right to Conduct Activities. The Company acknowledges that certain of the Investors are in the business of venture capital investing and therefore review the business plans and related proprietary information of many enterprises, including
enterprises which may have products or services which compete directly or indirectly with those of the Company. Nothing in this Agreement shall preclude or in any way restrict the Investors from investing or participating in any particular
enterprise whether or not such enterprise has products or services which compete with those of the Company. The Company hereby agrees and acknowledges that such Investors (together with their affiliates) invest in numerous portfolio companies, some
of which may be deemed competitive with the Company’s business (as currently conducted or as currently propose to be conducted). The Company hereby agrees that, to the extent permitted under applicable law, such Investors shall not be liable to
the Company for any claim arising out of, or based upon, (i) the investment by such Investors in any entity competitive with the Company, or (ii) actions taken by any partner, officer or other representative of such Investors to assist any
such competitive company, whether or not such action was taken as a member of the board of directors of such competitive company or otherwise, and whether or not such action has a detrimental effect on the Company; provided, however, that the
foregoing shall not relieve (x) any of the Investors from liability associated with the unauthorized disclosure of the Company’s confidential information obtained pursuant to this Agreement, or (y) any director or officer of the
Company from any liability associated with his or her fiduciary duties to the Company. 
 5.10 Termination of Covenants. The covenants
set forth in this Section 5, except for Subsection 5.7, shall terminate and be of no further force or effect (i) immediately before the consummation of the IPO, (ii) when the Company first becomes subject
to the periodic reporting requirements of Section 12(g) or 15(d) of the Exchange Act, or (iii) immediately before a Deemed Liquidation Event, as such term is defined in the Company’s Certificate of Incorporation, whichever event
occurs first. 

  
 21 








 6. Miscellaneous. 

6.1 Successors and Assigns. The rights under this Agreement may be assigned (but only with all related obligations) by a Holder to a
transferee of Registrable Securities that (i) is an Affiliate of a Holder; (ii) is a Holder’s Immediate Family Member or trust for the benefit of an individual Holder or one or more of such Holder’s Immediate Family Members; or
(iii) after such transfer, holds at least 100,000 shares of Registrable Securities (subject to appropriate adjustment for stock splits, stock dividends, combinations, and other recapitalizations); provided, however, that (x) the Company
is, within a reasonable time after such transfer, furnished with written notice of the name and address of such transferee and the Registrable Securities with respect to which such rights are being transferred; and (y) such transferee agrees in
a written instrument delivered to the Company to be bound by and subject to the terms and conditions of this Agreement, including the provisions of Subsection 2.11. For the purposes of determining the number of shares of Registrable
Securities held by a transferee, the holdings of a transferee (1) that is an Affiliate or stockholder of a Holder; (2) who is a Holder’s Immediate Family Member; or (3) that is a trust for the benefit of an individual Holder or
such Holder’s Immediate Family Member shall be aggregated together and with those of the transferring Holder; provided further that all transferees who would not qualify individually for assignment of rights shall have a single attorney-in-fact for the purpose of exercising any rights, receiving notices, or taking any action under this Agreement. The terms and conditions of this Agreement inure to
the benefit of and are binding upon the respective successors and permitted assignees of the parties. Nothing in this Agreement, express or implied, is intended to confer upon any party other than the parties hereto or their respective successors
and permitted assignees any rights, remedies, obligations or liabilities under or by reason of this Agreement, except as expressly provided herein. 

6.2 Governing Law. This Agreement and any controversy arising out of or relating to this Agreement shall be governed by and construed in
accordance with the internal laws of the Commonwealth of Massachusetts, without regard to conflict of law principles that would result in the application of any law other than the law of the Commonwealth of Massachusetts. 

6.3 Counterparts. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of
which together shall constitute one and the same instrument. Counterparts may be delivered via facsimile, electronic mail (including pdf or any electronic signature complying with the U.S. federal ESIGN Act of 2000, e.g., www.docusign.com) or other
transmission method and any counterpart so delivered shall be deemed to have been duly and validly delivered and be valid and effective for all purposes. 

6.4 Titles and Subtitles. The titles and subtitles used in this Agreement are for convenience only and are not to be considered in
construing or interpreting this Agreement. 
 6.5 Notices. All notices and other communications given or made pursuant to this
Agreement shall be in writing and shall be deemed effectively given upon the earlier of actual receipt or: (i) personal delivery to the party to be notified; (ii) when sent, if sent by electronic mail or facsimile during the
recipient’s normal business hours, and if not sent during normal business 

  
 22 








 
hours, then on the recipient’s next business day; (iii) five (5) days after having been sent by registered or certified mail, return receipt requested, postage prepaid; or
(iv) one (1) business day after the business day of deposit with a nationally recognized overnight courier, freight prepaid, specifying next-day delivery, with written verification of receipt. All
communications shall be sent to the respective parties at their addresses as set forth on Schedule A hereto, or to the principal office of the Company at 620 Memorial Drive, Suite 200 West, Cambridge, MA, 02139, ATTN: Chief
Executive Officer, in the case of the Company, or to such email address, facsimile number, or address as subsequently modified by written notice given in accordance with this Subsection 6.5. If notice is given to the Company, a copy (which
shall not constitute notice) shall also be given to Peter N. Handrinos, Latham & Watkins LLP, 200 Clarendon Street, Boston, Massachusetts 02116, (617) 948-6001 (fax), peter.handrinos@lw.com. 

6.6 Amendments and Waivers. Any term of this Agreement may be amended and the observance of any term of this Agreement may be waived
(either generally or in a particular instance, and either retroactively or prospectively) only with the written consent of the Company and the holders of a majority of the Registrable Securities then outstanding; provided that the
Company may in its sole discretion waive compliance with Subsection 2.12(c) (and the Company’s failure to object promptly in writing after notification of a proposed assignment allegedly in violation of Subsection 2.12(c) shall be
deemed to be a waiver); and provided further that any provision hereof may be waived by any waiving party on such party’s own behalf, without the consent of any other party. Notwithstanding the foregoing, this Agreement may not be amended or
terminated and the observance of any term hereof may not be waived with respect to any Investor without the written consent of such Investor, unless such amendment, termination, or waiver applies to all Investors in the same fashion (it being agreed
that a waiver of the provisions of Section 4 with respect to a particular transaction shall be deemed to apply to all Investors in the same fashion if such waiver does so by its terms, notwithstanding the fact that certain
Investors may nonetheless, by agreement with the Company, purchase securities in such transaction). The Company shall give prompt notice of any amendment or termination hereof or waiver hereunder to any party hereto that did not consent in writing
to such amendment, termination, or waiver. Any amendment, termination, or waiver effected in accordance with this Subsection 6.6 shall be binding on all parties hereto, regardless of whether any such party has consented thereto. No waivers of
or exceptions to any term, condition, or provision of this Agreement, in any one or more instances, shall be deemed to be or construed as a further or continuing waiver of any such term, condition, or provision. 

6.7 Severability. In case any one or more of the provisions contained in this Agreement is for any reason held to be invalid, illegal or
unenforceable in any respect, such invalidity, illegality, or unenforceability shall not affect any other provision of this Agreement, and such invalid, illegal, or unenforceable provision shall be reformed and construed so that it will be valid,
legal, and enforceable to the maximum extent permitted by law. 
 6.8 Aggregation of Stock. All shares of Registrable Securities held
or acquired by Affiliates shall be aggregated together for the purpose of determining the availability of any rights under this Agreement and such Affiliated persons may apportion such rights as among themselves in any manner they deem appropriate.


  
 23 








 6.9 Additional Investors. Notwithstanding anything to the contrary contained herein, if
the Company issues additional shares of Preferred Stock on or after the date hereof, whether pursuant to the Purchase Agreement or otherwise, any purchaser of such shares of Preferred Stock may become a party to this Agreement by executing and
delivering an additional counterpart signature page to this Agreement, and thereafter shall be deemed an “Investor” for all purposes hereunder. No action or consent by the Investors shall be required for such joinder to this Agreement by
such additional Investor, so long as such additional Investor has agreed in writing to be bound by all of the obligations as an “Investor” hereunder, and the Company may amend Schedule A to add such additional purchaser as an
Investor without requiring the consent of any other party hereto. 
 6.10 Entire Agreement. This Agreement (including any Schedules
and/or Exhibits hereto) constitutes the full and entire understanding and agreement among the parties with respect to the subject matter hereof, and any other written or oral agreement relating to the subject matter hereof existing between the
parties is expressly canceled. Upon the effectiveness of this Agreement, the Prior Agreement shall be deemed amended and restated and superseded and replaced in its entirety by this Agreement, and shall be of no further force or effect. 

6.11 Dispute Resolution. The parties (a) hereby irrevocably and unconditionally submit to the jurisdiction of the state courts of
the Commonwealth of Massachusetts and to the jurisdiction of the United States District Court for the District of Massachusetts for the purpose of any suit, action or other proceeding arising out of or based upon this Agreement, (b) agree not
to commence any suit, action or other proceeding arising out of or based upon this Agreement except in the state courts of the Commonwealth of Massachusetts or the United States District Court for the District of Massachusetts, and (c) hereby
waive, and agree not to assert, by way of motion, as a defense, or otherwise, in any such suit, action or proceeding, any claim that it is not subject personally to the jurisdiction of the above-named courts, that its property is exempt or immune
from attachment or execution, that the suit, action or proceeding is brought in an inconvenient forum, that the venue of the suit, action or proceeding is improper or that this Agreement or the subject matter hereof may not be enforced in or by such
court. 
 6.12 Waiver of Jury Trial. EACH PARTY HEREBY WAIVES ITS RIGHTS TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR
ARISING OUT OF THIS AGREEMENT, THE OTHER TRANSACTION DOCUMENTS, THE SECURITIES OR THE SUBJECT MATTER HEREOF OR THEREOF. THE SCOPE OF THIS WAIVER IS INTENDED TO BE ALL-ENCOMPASSING OF ANY AND ALL DISPUTES THAT
MAY BE FILED IN ANY COURT AND THAT RELATE TO THE SUBJECT MATTER OF THIS TRANSACTION, INCLUDING, WITHOUT LIMITATION, CONTRACT CLAIMS, TORT CLAIMS (INCLUDING NEGLIGENCE), BREACH OF DUTY CLAIMS, AND ALL OTHER COMMON LAW AND STATUTORY CLAIMS. THIS
SECTION HAS BEEN FULLY DISCUSSED BY EACH OF THE PARTIES HERETO AND THESE PROVISIONS WILL NOT BE SUBJECT TO ANY EXCEPTIONS. EACH PARTY HERETO HEREBY FURTHER WARRANTS AND REPRESENTS THAT SUCH PARTY HAS REVIEWED THIS WAIVER WITH ITS LEGAL COUNSEL, AND
THAT SUCH PARTY KNOWINGLY AND VOLUNTARILY WAIVES ITS JURY TRIAL RIGHTS FOLLOWING CONSULTATION WITH LEGAL COUNSEL. 

  
 24 








 6.13 Delays or Omissions. No delay or omission to exercise any right, power, or remedy
accruing to any party under this Agreement, upon any breach or default of any other party under this Agreement, shall impair any such right, power, or remedy of such nonbreaching or nondefaulting party, nor shall it be construed to be a waiver of or
acquiescence to any such breach or default, or to any similar breach or default thereafter occurring, nor shall any waiver of any single breach or default be deemed a waiver of any other breach or default theretofore or thereafter occurring. All
remedies, whether under this Agreement or by law or otherwise afforded to any party, shall be cumulative and not alternative. 
 6.14
Further Assurances. At any time or from time to time after the date hereof, the parties agree to cooperate with each other, and at the request of any other party, to execute and deliver any further instruments or documents and to take all
such further action as the other party may reasonably request in order to evidence or effectuate the consummation of the transactions contemplated hereby and to otherwise carry out the intent of the parties hereunder. 

6.15 Acknowledgment. The Company acknowledges that each Investor is in the business of venture capital investing and therefore reviews
the business plans and related proprietary information of many enterprises, including enterprises which may have products or services which compete directly or indirectly with those of the Company. Nothing in this Agreement shall preclude or in any
way restrict any Investor from investing or participating in any particular enterprise whether or not such enterprise has products or services which compete with those of the Company. 

[Remainder of Page Intentionally Left Blank] 

  
 25 








 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
	EVELO BIOSCIENCES, INC.
		
	By:	 	 /s/ Balkrishan (Simba) Gill, Ph.D.

	Name: Balkrishan (Simba) Gill, Ph.D.
	Title: President and Chief Executive Officer


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
	        INVESTORS:
	
	FLAGSHIP VENTURES FUND IV, L.P.
	FLAGSHIP VENTURES FUND IV-RX, L.P.
		
		 	Each by its General Partner,
		 	Flagship Ventures Fund IV General Partner LLC
		
	By:	 	 /s/ Noubar B. Afeyan, Ph.D.

		 	Name: Noubar B. Afeyan, Ph.D.
		 	Title: Manager
	
	FLAGSHIP VENTURES FUND V, L.P.
	FLAGSHIP V VENTURELABS RX FUND, L.P.
	NUTRITIONAL HEALTH DISRUPTIVE INNOVATION FUND, L.P.
	NUTRITIONAL HEALTH SIDE FUND, L.P.
		
		 	Each by its General Partner,
		 	Flagship Ventures Fund V General Partner LLC
		
	By:	 	 /s/ Noubar B. Afeyan, Ph.D.

		 	Name: Noubar B. Afeyan, Ph.D.
		 	Title: Manager
	
	FLAGSHIP VENTURES OPPORTUNITIES FUND I, L.P.
		
		 	By its General Partner,
		 	Flagship Ventures Opportunities Fund I General Partner LLC
		
	By:	 	 /s/ Noubar B. Afeyan, Ph.D.

		 	Name: Noubar B. Afeyan, Ph.D.
		 	Title: Member


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
		 	INVESTORS:
	
	MAYO CLINIC
		
	By:	 	 /s/ Harry N. Hoffman

		 	Name: Harry N. Hoffman
		 	Title: Treasurer & Co-Chief Investment Officer


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
		 	INVESTORS:
	
	GHF INC.
		
	By:	 	 /s/ Theo Melas-Kyriazi

		 	Name: Theo Melas-Kyriazi
		 	Title:   Director


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
		 	INVESTORS:
	
	CELGENE SWITZERLAND LLC
		
	By:	 	 /s/ Kevin Mello

		 	Name: Kevin Mello
		 	Title: Manager


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
		 	INVESTORS:
	
	GV 2016, L.P.
		
		 	By: GV 2016 GP, L.P., its General Partner
		 	By: GV 2016 GP, L.L.C., its General Partner
		
	By:	 	 /s/ Daphne M. Chang

		 	Name: Daphne M. Chang
		 	Title: Authorized Signatory
	
	GV 2017, L.P.
		
		 	By: GV 2017 GP, L.P., its General Partner
		 	By: GV 2017 GP, L.L.C., its General Partner
		
	By:	 	 /s/ Daphne M. Chang

		 	Name: Daphne M. Chang
		 	Title: Authorized Signatory


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
		 	INVESTORS:
	
	LEICHESTER FINANCE LIMITED
		
	By:	 	 /s/ Harald McPike

		 	Name:
		 	Title:


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
		 	INVESTORS:
	
	ALEXANDRIA VENTURE INVESTMENTS, LLC,
	a Delaware limited liability company
		
		 	By: ALEXANDRIA REAL ESTATE EQUITIES, INC., a Maryland corporation, managing member
		
	By:	 	 /s/ Aaron Jacobson

		 	Name: Aaron Jacobson
		 	Title: VP – Corporate Counsel


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
		 	    INVESTORS:
	
	 /s/ Bhagwant Gill    /s/ Krishna Gill

	Bhagwant and Krishna Gill, jointly


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
		 	INVESTORS:
	
	DEMENTIA DISCOVERY LP
		
		 	By: Dementia Discovery GP LP, Its Sole General Partner
		
		 	By: Dementia Discovery General Partner LLP,
		 	Its Sole General Partner
		
	By:	 	 /s/ Nick Coleman

		 	Name: Nick Coleman
		 	Title: Member
	
	DDF PARALLEL LLP
		
		 	By: Dementia Discovery General Partner LLP, Its Managing Member
		
	By:	 	 /s/ Nick Coleman

		 	Name: Nick Coleman
		 	Title: Member


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date first written above. 
  

			
		 	INVESTORS:
	
	SMRS-TOPE LLC
		
		 	By: HVST-TOPE LLC,
		 	Its Managing Member
		
		 	By: HarbourVest Partners L.P.
		 	Its Manager
		
		 	By: HarbourVest Partners, LLC
		 	Its General Partner
		
	By:	 	 /s/ Alex A. Rogers

		 	Name: Alex A. Rogers
		 	Title: Managing Director


 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 

  
 36 








 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated Investors’
Rights Agreement as of the date set forth below. 
  

							
		 		 	INVESTORS:
			
		 		 	FIDELITY MT. VERNON STREET TRUST:
		 		 	FIDELITY SERIES GROWTH COMPANY FUND
				
	Date: March 9, 2018	 		 	By:	 	 /s/ Colm Hogan

		 		 	Name:	 	Colm Hogan
		 		 	Title:	 	Authorized Signatory
			
		 		 	FIDELITY GROWTH COMPANY COMMINGLED POOL
			
		 		 	By: Fidelity Management Trust Company, as Trustee
				
	Date: March 9, 2018	 		 	By:	 	 /s/ Colm Hogan

		 		 	Name:	 	Colm Hogan
		 		 	Title:	 	Authorized Signatory
			
		 		 	FIDELITY MT. VERNON STREET TRUST:
		 		 	FIDELITY GROWTH COMPANY FUND
				
	Date: March 9, 2018	 		 	By:	 	 /s/ Colm Hogan

		 		 	Name:	 	Colm Hogan
		 		 	Title:	 	Authorized Signatory

 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 IN WITNESS WHEREOF, the parties have executed this Fourth Amended and Restated. Investors’
Rights Agreement as of the date set forth below. 

							
		 		 	INVESTORS:
			
		 		 	 THE TRUSTEES OF COLUMBIA

UNIVERSITY IN THE CITY OF NEW YORK

				
	Date: March 9, 2018	 		 	By:	 	 /s/ Sanjeev Daga

		 		 	Name:	 	Sanjeev Daga, Chief Operating Officer
		 		 	Title:	 	Columbia Investment Management Company, L.L.C.

 SIGNATURE PAGE TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 







 SCHEDULE A 

Investors 
  

			
	 Flagship Ventures Fund V, L.P.
 c/o Flagship
Pioneering
 55 Cambridge Parkway, 8th Floor

Cambridge, MA 02142
 T: XXXXXX

F: XXXXXX
 Email: XXXXXX
	  	 Alexandria Venture Investments, LLC
 385 East
Colorado Boulevard, Suite 299
 Pasadena, CA 91101
 T:
XXXXXX
 Email: XXXXXXXX

		
	 Flagship V VentureLabs Rx Fund, L.P.
 c/o
Flagship Pioneering
 55 Cambridge Parkway, 8th Floor

Cambridge, MA 02142
 T: XXXXXX

F: XXXXXX
 Email: XXXXXX
	  	 Bhagwant and Krishna Gill
 P.O. Box 6296

Sharjah, UAE
 Email: XXXXXX

XXXXXXXX

		
	 Nutritional Health Side Fund, L.P.
 c/o Flagship
Pioneering
 55 Cambridge Parkway, 8th Floor

Cambridge, MA 02142
 T: XXXXXX

F: XXXXXX
 Email: XXXXXX
	  	 Flagship Ventures Opportunities Fund I, L.P
 c/o
Flagship Pioneering
 55 Cambridge Parkway, 8th Floor

Cambridge, MA 02142
 T: XXXXXX

F: XXXXXX
 Email: XXXXXX

		
	 Flagship Ventures Fund IV, L.P.
 c/o Flagship
Pioneering
 55 Cambridge Parkway, 8th Floor

Cambridge, MA 02142
 T: XXXXXX

F: XXXXXX
 Email: XXXXXX
	  	 Mayo Clinic
 200 First Street SW

Rochester, MN 55905
 Attn: Treasury Services

Email: XXXXXX

		
	 Flagship Ventures Fund IV-Rx, L.P.

c/o Flagship Pioneering
 55 Cambridge Parkway, 8th Floor
 Cambridge, MA 02142

T: XXXXXX
 F: XXXXXX

Email: XXXXXX
  

Nutritional Health Disruptive Innovation Fund, L.P.
 c/o Flagship
Pioneering
 55 Cambridge Parkway, 8th Floor

Cambridge, MA 02142
 T: XXXXXX

F: XXXXXX
 Email: XXXXXX
	  	 GHF Inc.
 190 Elgin Avenue

George Town, Grand Cayman KY1-9005

Cayman Islands
 Email: XXXXXX

XXXXXX
  
  

With a notice to:
  

c/o Mr. Theo Melas-Kyriazi
 15 Norfolk Road

Chestnut Hill, MA 02467
 Email: XXXXXX

XXXXXX










			
	 Celgene Switzerland LLC
 AON House

30 Woodbourne Ave
 Pemborke HM 08

Bermuda
 Attention: Kevin Mello

T: XXXXXX
 Email: XXXXXX
	  	 GV 2016, L.P.
 Attn: GV Legal Department

1600 Amphitheatre Parkway
 Mountain View, CA 94043

Email: XXXXXX

		
	 Leichester Finance Limited
 C/O Trident
Chambers
 PO Box 146
 Road Town

Tortola
 British Virgin Islands

T: XXXXXX
 F: XXXXXX

Email: XXXXXX
	  	 GV 2017, L.P.
 Attn: GV Legal Department

1600 Amphitheatre Parkway
 Mountain View, CA 94043

Email: XXXXXX

		
	 Dementia Discovery LP
 71 Kingsway

London
 WC2B 6ST

UK
 Email: XXXXXX

XXXXXX
 T: XXXXXX

F: XXXXXX
	  	 DF Parallel LLP
 71 Kingsway

London
 WC2B 6ST

UK
 Email: XXXXXX

XXXXXX
 T: XXXXXX

F: XXXXXX

		
	 SMRS-TOPE LLC
 c/o HarbourVest Partners, LLC

One Financial Center, 44th Floor
 Boston, MA 02111

Attention: Lenny Li
 Email: XXXXXX

Fax: XXXXXX
  

with copy to:
  

Debevoise & Plimpton LLP
 919 Third Avenue

New York, New York 10022
 Attention: David J. Schwartz

Email: XXXXXX
 Facsimile: XXXXXX
	  	









			
	Fidelity Mt. Vernon Street Trust: Fidelity	  	Fidelity Growth Company Commingled Pool
	Series Growth Company Fund	  	Mag & Co.
	State Street Bank & Trust	  	c/o Brown Brothers Harriman & Co.
	PO Box 5756	  	Attn: Corporate Actions /Vault
	Boston, Massachusetts 02206	  	140 Broadway
	Attn: WAVELENGTH + CO Fidelity Mt.	  	New York, NY 10005
	Vernon Street Trust: Fidelity Series Growth Company Fund	  	BBH.Fidelity.CA.Notifications@BBH.com
	Email: SSBCORPACTIONS@StateStreet.com	  	
	Fax number: 617-988-9110	  	
		
	Fidelity Mt. Vernon Street Trust: Fidelity	  	The Trustees of Columbia University in the
	Growth Company Fund	  	City of New York
	BNY Mellon	  	405 Lexington Avenue, 63rd Floor
	Attn: Stacey Wolfe	  	New York, NY 10174
	525 William Penn Place Rm 0400	  	Attn: Sanjeev K. Daga
	Pittsburgh, PA 15259	  	T: (212) 851-2051
	Email: FidelityCorporateEvents@bnymellon.com	  	F: (212) 851-2040
	Fax number: 412-236-1012	  	








 AMENDMENT NO. 1 

TO 
 FOURTH AMENDED AND
RESTATED INVESTORS’ RIGHTS AGREEMENT 
 THIS AMENDMENT NO. 1 TO FOURTH AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT
(this “Amendment”) is made and entered into as of April 30, 2018, by and among Evelo Biosciences, Inc., a Delaware corporation (the “Company”), and the undersigned parties to that certain Fourth Amended and
Restated Investors’ Rights Agreement, dated as of February 9, 2018 (as amended, the “Agreement”), by and among the Company and the investors named therein; 

WHEREAS, pursuant to Section 6.6 of the Agreement, the Agreement may be amended by written agreement of the Company and the
holders of a majority of the Registrable Securities then outstanding (collectively, the “Requisite Parties”); 

WHEREAS, the Company and the undersigned parties to the Agreement constitute the Requisite Parties; and 

WHEREAS, the parties hereto desire to amend the Agreement as set forth herein. 

NOW, THEREFORE, for good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the parties hereto
hereby covenant and agree to be bound as follows: 
 Section 1. Capitalized Terms. Capitalized terms used herein and not
otherwise defined herein shall have the respective meanings assigned to them in the Agreement. 
 Section 2. Amendment.
Subsection 1.20 of the Agreement is hereby amended and restated in its entirety to read as follows: 
 ““Registrable
Securities” means (i) the Common Stock issuable or issued upon conversion of the Preferred Stock; (ii) any Common Stock, or any Common Stock issued or issuable (directly or indirectly) upon conversion and/or exercise of any other
securities of the Company, held by the Investors as of the date of the effectiveness of the Company’s Registration Statement on Form S-1 (Reg. No. 333-224278)
filed by the Company under the Securities Act; (iii) the Common Stock acquired by the Investors in the IPO, provided, however, that for the purpose of Subsection 6.6 of this Agreement, Common Stock acquired in the IPO shall not be deemed
Registrable Securities; and (iv) any Common Stock issued as (or issuable upon the conversion or exercise of any warrant, right, or other security that is issued as) a dividend or other distribution with respect to, or in exchange for or in
replacement of, the shares referenced in clause (i), (ii) and (iii) above; excluding in all cases, however, any Registrable Securities sold by a Person in a transaction in which the applicable rights under
this Agreement are not assigned pursuant to Subsection 6.1, and excluding for purposes of Section 2 and, following the consummation of the IPO, Subsection 6.6, any shares for which registration rights
have terminated pursuant to Subsection 2.13 of this Agreement.” 
 Section 3. No Other Amendments; Conflicts. No
term or provision of the Agreement shall be affected by this Amendment, unless specifically set forth herein and any term or provision not affected by this Amendment shall remain in full force and effect following the date hereof. In the event of a
conflict between the terms of the Agreement and the terms of this Amendment, the terms of this Amendment shall control. 







 Section 4. Governing Law. This Amendment shall be governed by, and construed
and enforced in accordance with, the internal laws of the Commonwealth of Massachusetts, without regard to conflict of law principles that would result in the application of any law other than the law of the Commonwealth of Massachusetts. 

Section 5. Captions; Pronouns. All articles and section headings or captions contained in this Amendment are inserted only as a
matter of convenience and for reference and in no way define, limit, extend or describe the scope of this Amendment or the intent of any provision thereof. References in the Agreement to the Agreement shall mean the Agreement, as amended by this
Amendment. 
 Section 6. Severability. If any provision of this Amendment or application to any party or circumstance shall be
determined by any court of competent jurisdiction to be invalid or unenforceable to any extent, the remainder of this Amendment or the application of such provision to any other party or circumstances shall not be affected thereby, and each
provision shall be valid and shall be enforced to the fullest extent permitted by law. 
 Section 7. Counterparts. This
Amendment may be executed in multiple counterparts, each of which shall be deemed an original, but all of which taken together shall constitute one and the same instrument. The exchange of copies of this Amendment and of signature pages by facsimile
transmission or other electronic means shall constitute effective execution and delivery of this Amendment as to the parties and may be used in lieu of the original Amendment for all purposes. 

[Signature Pages Follows] 







 IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed as of the
date first written above. 
  

			
	EVELO BIOSCIENCES, INC.
		
	By:	 	 /s/ Balkrishan (Simba) Gill, Ph.D.

	Name:	 	Balkrishan (Simba) Gill, Ph.D.
	Title:	 	President and Chief Executive Officer



  
 Signature Page to
Amendment No. 1 to Fourth Amended and Restated Investors’ Rights Agreement 








 
			
	INVESTORS:
	
	FLAGSHIP VENTURES FUND IV, L.P.
	FLAGSHIP VENTURES FUND IV-RX, L.P.
		
		 	Each by its General Partner,
		 	Flagship Ventures Fund IV General Partner LLC
		
	By:	 	 /s/ Noubar B. Afeyan, Ph.D.

		 	Name: Noubar B. Afeyan, Ph.D.
		 	Title: Manager


  

			
	FLAGSHIP VENTURES FUND V, L.P.
	FLAGSHIP V VENTURELABS RX FUND, L.P.
	NUTRITIONAL HEALTH DISRUPTIVE INNOVATION FUND, L.P.
	NUTRITIONAL HEALTH SIDE FUND, L.P.
		
		 	Each by its General Partner,
		 	Flagship Ventures Fund V General Partner LLC
		
	By:	 	 /s/ Noubar B. Afeyan, Ph.D.

		 	Name: Noubar B. Afeyan, Ph.D.
		 	Title: Manager


  

			
	FLAGSHIP VENTURES OPPORTUNITIES FUND I, L.P.
		
		 	By its General Partner,
		 	Flagship Ventures Opportunities Fund I General Partner LLC
		
	By:	 	 /s/ Noubar B. Afeyan, Ph.D.

		 	Name: Noubar B. Afeyan, Ph.D.
		 	Title: Member



  
 Signature Page to
Amendment No. 1 to Fourth Amended and Restated Investors’ Rights Agreement 








 
			
	MAYO CLINIC
		
	By:	 	  

		 	Name:
		 	Title:
	
	GHF INC.
		
	By:	 	  

		 	Name: Theo Melas-Kyriazi
		 	Title: Director
	
	CELGENE SWITZERLAND LLC
		
	By:	 	  

		 	Name:
		 	Title:
	
	GV 2016, L.P.
		
		 	By: GV 2016 GP, L.P., its General Partner
		 	By: GV 2016 GP, L.L.C., its General Partner
		
	By:	 	  

		 	Name: Daphne M. Chang
		 	Title: Authorized Signatory
	
	GV 2017, L.P.
		
		 	By: GV 2017 GP, L.P., its General Partner
		 	By: GV 2017 GP, L.L.C., its General Partner
		
	By:	 	  

		 	Name: Daphne M. Chang
		 	Title: Authorized Signatory



  
 Signature Page to
Amendment No. 1 to Fourth Amended and Restated Investors’ Rights Agreement 








 
			
	LEICHESTER FINANCE LIMITED
		
	By:	 	  

		 	Name:
		 	Title:



  
 Signature Page to
Amendment No. 1 to Fourth Amended and Restated Investors’ Rights Agreement 








 
			
	 ALEXANDRIA VENTURE INVESTMENTS, LLC,

a Delaware limited liability company

		
		 	 By: ALEXANDRIA REAL ESTATE EQUITIES, INC.,

a Maryland corporation, managing member

		
	By:	 	  

		 	Name:
		 	Title:
	 
	Bhagwant and Krishna Gill, jointly
	
	DEMENTIA DISCOVERY LP
		
		 	By: Dementia Discovery GP LP, Its Sole General Partner
		
		 	 By: Dementia Discovery General Partner LLP,

Its Sole General Partner

		
	By:	 	  

		 	Name:
		 	Title:
	
	DDF PARALLEL LLP
		
		 	By: Dementia Discovery General Partner LLP, Its Managing Member
		
	By:	 	  

		 	Name:
		 	Title:



  
 Signature Page to
Amendment No. 1 to Fourth Amended and Restated Investors’ Rights Agreement 








 
			
	SMRS-TOPE LLC
		
		 	By: HVST-TOPE LLC,
		 	Its Managing Member
		
		 	By: HarbourVest Partners L.P.
		 	Its Manager
		
		 	By: HarbourVest Partners, LLC
		 	Its General Partner
		
	By:	 	  

		 	Name:
		 	Title:
	
	 FIDELITY MT. VERNON STREET TRUST:

FIDELITY SERIES GROWTH COMPANY FUND

		
	By:	 	  

	 Name: 

	Title: 
	
	FIDELITY GROWTH COMPANY COMMINGLED POOL
	
	By: Fidelity Management Trust Company, as Trustee
		
	By:	 	  

	 Name: 

	Title: 
	
	FIDELITY MT. VERNON STREET TRUST: FIDELITY GROWTH COMPANY FUND
		
	By:	 	  

	 Name: 

	 Title: 




  
 Signature Page to
Amendment No. 1 to Fourth Amended and Restated Investors’ Rights Agreement