EX-10.2




 Exhibit 10.2 

REGISTRATION RIGHTS AGREEMENT 

This Registration Rights Agreement (this “Agreement”) is made and entered into as of August 12, 2022, by and between
Vigil Neuroscience, Inc., a Delaware corporation (the “Company”), and each of the several purchasers signatory hereto (each such purchaser, a “Purchaser” and, collectively, the “Purchasers”). 

This Agreement is made pursuant to the Securities Purchase Agreement, dated as of the date hereof, between the Company and each Purchaser (the
“Purchase Agreement”). 
 The Company and each Purchaser hereby agree as follows: 

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

“Advice” shall have the meaning set forth in Section 6(d). 

“Effectiveness Date” means, with respect to the Initial Registration Statement required to be filed hereunder, the 40th calendar day following the Filing Date (or, in the event of a “full review” by the Commission, the 75th calendar day following the
Filing Date) and with respect to any additional Registration Statements which may be required pursuant to Section 2(c) or Section 3(c), the 45th calendar day following the date on which an additional Registration Statement is required to
be filed hereunder (or, in the event of a “full review” by the Commission, the 75th calendar day following the date such additional Registration Statement is required to be filed hereunder); provided, however, that in the
event the Company is notified by the Commission that one or more of the above Registration Statements will not be reviewed or is no longer subject to further review and comments, the Effectiveness Date as to such Registration Statement shall be the
fifth Trading Day following the date on which the Company is so notified if such date precedes the dates otherwise required above, provided, further, if such Effectiveness Date falls on a day that is not a Trading Day, then the Effectiveness Date
shall be the next succeeding Trading Day. 
 “Effectiveness Period” shall have the meaning set forth in Section 2(a).

 “Event” shall have the meaning set forth in Section 2(d). 

“Event Date” shall have the meaning set forth in Section 2(d). 

“Filing Date” means, with respect to the Initial Registration Statement required hereunder, the 60th calendar day following the date hereof; provided, however, that if such day falls on a day that is not a Trading Day, then the Filing Date shall be the next succeeding Trading Day, and, with respect
to any additional Registration Statements which may be required pursuant to Section 2(c) or Section 3(c), the earliest practical date on which the Company is permitted by SEC Guidance to file such additional Registration Statement related
to the Registrable Securities. 
 “Holder” or “Holders” means the holder or holders, as the case may be,
from time to time of Registrable Securities. 
 “Indemnified Party” shall have the meaning set forth in Section 5(c).

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

“Initial Registration Statement” means the initial Registration Statement filed pursuant to this Agreement. 

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

“Plan of Distribution” shall have the meaning set forth in Section 2(a). 











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

“Registrable Securities” means, as of any date of determination, (a) all Shares, (b) all Warrant Shares then issued
and issuable upon exercise of the Pre-Funded Warrants (assuming on such date the Pre-Funded Warrants are exercised in full without regard to any exercise limitations
therein) and (c) any securities issued or then issuable upon any stock split, dividend or other distribution, recapitalization or similar event with respect to the foregoing; provided, however, that any such Registrable Securities
shall cease to be Registrable Securities (and the Company shall not be required to maintain the effectiveness of any, or file another, Registration Statement hereunder with respect thereto) for so long as (a) a Registration Statement with
respect to the sale of such Registrable Securities is declared effective by the Commission under the Securities Act and such Registrable Securities have been disposed of by the Holder in accordance with such effective Registration Statement,
(b) such Registrable Securities have been previously sold in accordance with Rule 144, or (c) such Registrable Securities become eligible for resale without volume or
manner-of-sale restrictions and without current public information pursuant to Rule 144, as reasonably determined by the Company, upon the advice of counsel to the
Company. 
 “Registration Statement” means any registration statement required to be filed hereunder pursuant to
Section 2(a) and any additional registration statements contemplated by Section 2(c) or Section 3(c), including (in each case) the Prospectus, amendments and supplements to any such registration statement or Prospectus, including pre- and post-effective amendments, all exhibits thereto, and all material incorporated by reference or deemed to be incorporated by reference in any such registration statement. 

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

“Rule 424” means Rule 424 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended or
interpreted from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same purpose and effect as such Rule. 

“Selling Stockholder Questionnaire” shall have the meaning set forth in Section 3(a). 

“SEC Guidance” means (i) any publicly-available written or oral guidance of the Commission staff, or any comments,
requirements or requests of the Commission staff and (ii) the Securities Act. 
 “Trading Market” means any of the
following markets or exchanges on which the shares of Common Stock are listed or quoted for trading on the date in question: the NYSE American, The Nasdaq Capital Market, The Nasdaq Global Market, The Nasdaq Global Select Market or the New York
Stock Exchange , OTCQB or OTCQX, or the “Pink Open Market” of OTC Markets Group, Inc. (or any successors to any of the foregoing). 
 2. Shelf
Registration. 
 (a) On or prior to each Filing Date, the Company shall prepare and file with the Commission a Registration Statement
covering the resale of all of the Registrable Securities that are not then registered on an effective Registration Statement for an offering to be made on a continuous basis pursuant to Rule 415. Each Registration Statement filed hereunder shall be
on Form S-3 (except if the Company is not then eligible to register for resale the Registrable Securities on Form S-3, in which case such registration shall be on
another appropriate form in accordance herewith, subject to the provisions of Section 2(e), including but not limited to a Registration Statement on Form S-1) and shall contain substantially the
“Plan of Distribution” attached hereto as Annex A and substantially the “Selling Stockholder” section attached hereto as Annex B; provided, however, that no Holder shall be required to be
named as an “underwriter” without such Holder’s express prior written consent. Subject to the terms of this Agreement, the Company shall use its commercially reasonable efforts to cause a Registration Statement filed under


  
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this Agreement (including, without limitation, under Section 3(c)) to be declared effective under the Securities Act as promptly as possible after the filing thereof, but in any event
no later than the applicable Effectiveness Date, and shall use its commercially reasonable efforts to keep such Registration Statement continuously effective under the Securities Act until the date that all Registrable Securities covered by such
Registration Statement (i) have been sold, thereunder or pursuant to Rule 144, or (ii) may be sold without volume or manner-of-sale restrictions
pursuant to Rule 144 and without the requirement for the Company to be in compliance with the current public information requirement under Rule 144 (the “Effectiveness Period”). The Company shall request in writing effectiveness of
a Registration Statement as of 5:00 p.m. (New York City time) on a Trading Day. The Company shall promptly notify the Holders via facsimile or by e-mail of the effectiveness of a Registration Statement on the
same Trading Day that the Company telephonically confirms effectiveness with the Commission, which shall be the date requested for effectiveness of such Registration Statement. The Company shall, by 10:00 p.m. (New York City time) on the Trading Day
after the effective date of such Registration Statement, file a final Prospectus with the Commission as required by Rule 424. Failure to so notify the Holder within one (1) Trading Day of such notification of effectiveness or failure to
file a final Prospectus as foresaid shall be deemed an Event under Section 2(d). 
 (b) Notwithstanding the registration
obligations set forth in Section 2(a), if the Commission informs the Company that all of the Registrable Securities cannot, as a result of the application of Rule 415, be registered for resale as a secondary offering on a single Registration
Statement, the Company agrees to promptly inform each of the Holders thereof and use its commercially reasonable efforts to file amendments to the Initial Registration Statement as required by the Commission, covering the maximum number of
Registrable Securities permitted to be registered by the Commission, on Form S-3 or such other form available to register for resale the Registrable Securities as a secondary offering, including but not
limited to a Form S-1; provided, however, that prior to filing such amendment, the Company shall be obligated to use diligent efforts to advocate with the Commission for the registration of all
of the Registrable Securities in accordance with the SEC Guidance, including without limitation, Compliance and Disclosure Interpretation 612.09. 

(c) Notwithstanding any other provision of this Agreement and subject to the payment of liquidated damages pursuant to Section 2(d), if
the Commission or any SEC Guidance sets forth a limitation on the number of Registrable Securities permitted to be registered on a particular Registration Statement as a secondary offering (and notwithstanding that the Company used reasonably
diligent efforts to advocate with the Commission for the registration of all or a greater portion of Registrable Securities), unless otherwise directed in writing by a Holder as to its Registrable Securities, the number of Registrable Securities to
be registered on such Registration Statement will be reduced as follows: 
 a. First, the Company shall reduce or eliminate any securities to
be included other than Registrable Securities; and 
 b. Second, the Company shall reduce Registrable Securities represented by Shares and
the Pre-Funded Warrants (applied, in the case that some Shares and the Pre-Funded Warrants may be registered, to the Holders on a pro rata basis based on the total
number of unregistered Shares and the Pre-Funded Warrants held by such Holders, except to the extent otherwise directed by the Commission). 

In the event of a cutback hereunder, the Company shall give the Holder at least three (3) Trading Days prior written notice along with
the calculations as to such Holder’s allotment. In the event the Company amends the Initial Registration Statement in accordance with the foregoing, the Company will use its reasonable best efforts to file with the Commission, as promptly as
allowed by the Commission or SEC Guidance provided to the Company or to registrants of securities in general, one or more registration statements on Form S-3 or such other form available to register for resale
those Registrable Securities that were not registered for resale on the Initial Registration Statement, as amended. Notwithstanding the foregoing, the Company shall not be obligated to pay liquidated damages pursuant to Section 2(d) with
respect to any Registrable Securities cut back pursuant to this Section 2(c). 
 (d) If: (i) the Initial Registration
Statement is not filed on or prior to its Filing Date, the Company shall be deemed to have not satisfied this clause (i), or (ii) the Company fails to file with the Commission a request for acceleration of a Registration Statement in accordance
with Rule 461 promulgated by the Commission pursuant to the Securities Act, within five (5) Trading Days of the date that the Company is notified (orally or in writing, whichever is earlier) by the Commission that such Registration Statement will
not be “reviewed” or will not be 

  
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subject to further review, or (iii) prior to the effective date of a Registration Statement, the Company fails to file any required pre-effective
amendment or otherwise submit any required response in writing to comments made by the Commission in respect of such Registration Statement within fifteen (15) Trading Days after the receipt of comments by or notice from the Commission that
such amendment is required in order for such Registration Statement to be declared effective or (iv) a Registration Statement registering for resale all of the Registrable Securities is not declared effective by the Commission by the
Effectiveness Date of the Initial Registration Statement for a reason reasonably attributed to the action or inaction of the Company, or (v) after the effective date of a Registration Statement, such Registration Statement ceases for any reason
reasonably attributed to the action or inaction of the Company to remain continuously effective as to all Registrable Securities included in such Registration Statement, or the Holders are otherwise not permitted to utilize the Prospectus therein to
resell such Registrable Securities, for more than fifteen (15) consecutive calendar days or more than an aggregate of twenty (20) calendar days (which need not be consecutive calendar days) during any
12-month period (any such failure or breach being referred to as an “Event”, and for purposes of clauses (i) and (iv), the date on which such Event occurs, and for purpose of clause
(ii) the date on which such five (5) Trading Day period is exceeded, and for purpose of clause (iii) the date which such fifteen (15) Trading Day period is exceeded, and for purpose of clause (v) the date on which
such fifteen (15) or twenty (20) calendar day period, as applicable, is exceeded being referred to as an “Event Date”), then, in addition to any other rights the Holders may have hereunder or under applicable law,
on each such Event Date and on each monthly anniversary of each such Event Date (if the applicable Event shall not have been cured by such date) until the applicable Event is cured, the Company shall pay to each Holder an amount in cash, as partial
liquidated damages and not as a penalty, equal to the product of 1.0% multiplied by the Aggregate Purchase Price paid by such Holder pursuant to the Purchase Agreement. The parties agree that the maximum aggregate liquidated damages payable to a
Holder under this Agreement shall be 5.0% of the Aggregate Purchase Price paid by such Holder pursuant to the Purchase Agreement for the Registrable Securities then held by such Holder. 

(e) If Form S-3 is not available for the registration of the resale of Registrable Securities
hereunder, the Company shall (i) register the resale of the Registrable Securities on another appropriate form and (ii) undertake to register the Registrable Securities on Form S-3 as soon as
such form is available; provided that the Company shall maintain the effectiveness of the Registration Statement then in effect until such time as a Registration Statement on Form S-3 covering the Registrable
Securities has been declared effective by the Commission. The Initial Registration Statement shall be filed on Form S-1, if Form S-3 is not available for the
registration of the resale of Registrable Securities hereunder. 
 (f) Notwithstanding anything to the contrary contained herein, in no
event shall the Company be permitted to name any Holder or affiliate of a Holder as an underwriter without the prior written consent of such Holder. 
 3.
Registration Procedures. 
 In connection with the Company’s registration obligations hereunder, the Company shall: 

(a) Not less than five (5) Trading Days prior to the filing of each Registration Statement and not less than one (1) Trading
Day prior to the filing of any related Prospectus or any amendment or supplement thereto (including any document that would be incorporated or deemed to be incorporated therein by reference), the Company shall (i) furnish to each Holder
copies of all such documents proposed to be filed, which documents (other than those incorporated or deemed to be incorporated by reference) will be subject to the review of such Holders, (ii) cause its officers and directors, counsel
and independent registered public accountants to respond to any inquiries as shall be necessary, in the reasonable opinion of respective counsel to each Holder, to conduct a reasonable investigation within the meaning of the Securities Act and
(iii) use its best efforts to reflect in each such document, when so filed with the Commission, such comments as each Holder reasonably proposed. Notwithstanding the above, the Company shall not be obligated to provide the Holders
advance copies of any universal shelf registration statement registering securities in addition to those required hereunder, or any Prospectus prepared thereto. Each Holder agrees to furnish to the Company a completed questionnaire in the form
attached to this Agreement as Annex C (a “Selling Stockholder Questionnaire”) on a date that is not later than the later of two (2) Trading Days prior to the Filing Date and the end of the fourth (4th) Trading Day
following the date on which such Holder receives draft materials in accordance with this Section. 

  
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 (b) (i) Prepare and file with the Commission such amendments, including post-effective
amendments, to a Registration Statement and the Prospectus used in connection therewith as may be necessary to keep a Registration Statement continuously effective as to the applicable Registrable Securities for the Effectiveness Period and prepare
and file with the Commission such additional Registration Statements in order to register for resale under the Securities Act all of the Registrable Securities, (ii) cause the related Prospectus to be amended or supplemented by any required
Prospectus supplement (subject to the terms of this Agreement), and, as so supplemented or amended, to be filed pursuant to Rule 424, (iii) respond as promptly as reasonably possible to any comments received from the Commission with respect to a
Registration Statement or any amendment thereto and provide as promptly as reasonably possible to the Holders true and complete copies of all correspondence from and to the Commission relating to a Registration Statement (provided that, the Company
shall excise any information contained therein which would constitute material non-public information regarding the Company or any of its Subsidiaries), and (iv) comply in all material respects with the
applicable provisions of the Securities Act and the Exchange Act with respect to the disposition of all Registrable Securities covered by a Registration Statement during the applicable period in accordance (subject to the terms of this Agreement)
with the intended methods of disposition by the Holders thereof set forth in such Registration Statement as so amended or in such Prospectus as so supplemented. 

(c) If during the Effectiveness Period, the number of Registrable Securities at any time exceeds 100% of the number of shares of Common Stock
then registered in a Registration Statement, then the Company shall file as soon as reasonably practicable, but in any case prior to the applicable Filing Date, an additional Registration Statement covering the resale by the Holders of not less than
the number of such Registrable Securities. 
 (d) Notify the Holders of Registrable Securities to be sold (which notice shall, pursuant to
clauses (iii) through (vi) hereof, be accompanied by an instruction to suspend the use of the Prospectus until the requisite changes have been made) as promptly as reasonably possible (and, in the case of (i)(A) below, not less than one
(1) Trading Day prior to such filing) and (if requested by any such Person) confirm such notice in writing no later than one (1) Trading Day following the day (i)(A) when a Prospectus or any Prospectus supplement or post-effective
amendment to a Registration Statement is proposed to be filed, (B) when the Commission notifies the Company whether there will be a “review” of such Registration Statement and whenever the Commission comments in writing on such
Registration Statement, and (C) with respect to a Registration Statement or any post-effective amendment, when the same has become effective, (ii) of any request by the Commission or any other federal or state governmental authority for
amendments or supplements to a Registration Statement or Prospectus or for additional information, (iii) of the issuance by the Commission or any other federal or state governmental authority of any stop order suspending the effectiveness of a
Registration Statement covering any or all of the Registrable Securities or the initiation of any Actions for that purpose, (iv) of the receipt by the Company of any notification with respect to the suspension of the qualification or exemption
from qualification of any of the Registrable Securities for sale in any jurisdiction, or the initiation or threatening of any Proceeding for such purpose, (v) of the occurrence of any event or passage of time that makes the financial statements
included in a Registration Statement ineligible for inclusion therein or any statement made in a Registration Statement or Prospectus or any document incorporated or deemed to be incorporated therein by reference untrue in any material respect or
that requires any revisions to a Registration Statement, Prospectus or other documents so that, in the case of a Registration Statement or the Prospectus, as the case may be, it will not contain any untrue statement of a material fact or omit to
state any material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading, and (vi) of the occurrence or existence of any pending corporate
development with respect to the Company that the Company believes may be material and that, in the determination of the Company, makes it not in the best interest of the Company to allow continued availability of a Registration Statement or
Prospectus; provided, however, that in no event shall any such notice contain any information which would constitute material, non-public information regarding the Company or any of its
Subsidiaries. 
 (e) Use its commercially reasonable efforts to avoid the issuance of, or, if issued, obtain the withdrawal of (i) any
order stopping or suspending the effectiveness of a Registration Statement, or (ii) any suspension of the qualification (or exemption from qualification) of any of the Registrable Securities for sale in any jurisdiction, at the earliest
practicable moment. 
 (f) Furnish to each Holder, without charge, at least one conformed copy of each such Registration Statement and each
amendment thereto, including financial statements and schedules, all documents incorporated or deemed to be incorporated therein by reference to the extent requested by such Person, and all exhibits to the extent requested by such Person (including
those previously furnished or incorporated by reference) promptly after the filing of such documents with the Commission, provided that any such item which is available on the EDGAR system (or successor thereto) need not be furnished in physical
form. 

  
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 (g) Subject to the terms of this Agreement, the Company hereby consents to the use of such
Prospectus and each amendment or supplement thereto by each of the selling Holders in connection with the offering and sale of the Registrable Securities covered by such Prospectus and any amendment or supplement thereto, except after the giving of
any notice pursuant to Section 3(d). 
 (h) Prior to any resale of Registrable Securities by a Holder, use its commercially reasonable
efforts to register or qualify or cooperate with the selling Holders in connection with the registration or qualification (or exemption from registration or qualification) of such Registrable Securities for the resale by the Holder under the
securities or Blue Sky laws of such jurisdictions within the United States as any Holder reasonably requests in writing, to keep each registration or qualification (or exemption therefrom) effective during the Effectiveness Period and to do any and
all other acts or things reasonably necessary to enable the disposition in such jurisdictions of the Registrable Securities covered by each Registration Statement, provided that the Company shall not be required to qualify generally to do business
in any jurisdiction where it is not then so qualified, subject the Company to any material tax in any such jurisdiction where it is not then so subject or file a general consent to service of process in any such jurisdiction. 

(i) If requested by a Holder, cooperate with such Holder to facilitate the timely preparation and delivery of certificates or book-entry
notations representing Registrable Securities to be delivered to a transferee pursuant to a Registration Statement, which certificates or book-entry notations shall be free, to the extent permitted by the Purchase Agreement, of all restrictive
legends, and to enable such Registrable Securities to be in such denominations and registered in such names as any such Holder may request. 

(j) Upon the occurrence of any event contemplated by Section 3(d), as promptly as reasonably possible under the circumstances taking into
account the Company’s good faith assessment of any adverse consequences to the Company and its stockholders of the premature disclosure of such event, prepare a supplement or amendment, including a post-effective amendment, to a Registration
Statement or a supplement to the related Prospectus or any document incorporated or deemed to be incorporated therein by reference, and file any other required document so that, as thereafter delivered, neither a Registration Statement nor such
Prospectus will contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading. If
the Company notifies the Holders in accordance with clauses (iii) through (vi) of Section 3(d) above to suspend the use of any Prospectus until the requisite changes to such Prospectus have been made, then the Holders shall suspend use of
such Prospectus. The Company will use its reasonable best efforts to ensure that the use of the Prospectus may be resumed as promptly as is practicable. The Company shall be entitled to exercise its right under this Section 3(j) to suspend the
availability of a Registration Statement and Prospectus, subject to the payment of partial liquidated damages otherwise required pursuant to Section 2(d), for a period not to exceed 60 calendar days (which need not be consecutive days) in any 12-month period. 
 (k) Otherwise use commercially reasonable efforts to comply with all applicable rules
and regulations of the Commission under the Securities Act and the Exchange Act, including, without limitation, Rule 172 under the Securities Act, file any final Prospectus, including any supplement or amendment thereof, with the Commission pursuant
to Rule 424 under the Securities Act, promptly inform the Holders in writing if, at any time during the Effectiveness Period, the Company does not satisfy the conditions specified in Rule 172 and, as a result thereof, the Holders are required to
deliver a Prospectus in connection with any disposition of Registrable Securities and take such other actions as may be reasonably necessary to facilitate the registration of the Registrable Securities hereunder. 

(l) The Company shall use commercially reasonable efforts to maintain eligibility for use of Form S-3
(or any successor form thereto) for the registration of the resale of Registrable Securities. 
 (m) The Company may require each selling
Holder to furnish to the Company a certified statement as to the number of shares of Common Stock beneficially owned by such Holder and, if required by the Commission, the natural persons thereof that have voting and dispositive control over the
shares. During any periods that the 

  
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Company is unable to meet its obligations hereunder with respect to the registration of the Registrable Securities solely because any Holder fails to furnish such information within three Trading
Days of the Company’s request, any liquidated damages that are accruing at such time as to such Holder only shall be tolled and any Event that may otherwise occur solely because of such delay shall be suspended as to such Holder only, until
such information is delivered to the Company. 
 4. Registration Expenses. 

All fees and expenses incident to the performance of or compliance with, this Agreement by the Company shall be borne by the Company whether or
not any Registrable Securities are sold pursuant to a Registration Statement. The fees and expenses referred to in the foregoing sentence shall include, without limitation, (i) all registration and filing fees (including, without limitation,
fees and expenses of the Company’s counsel and independent registered public accountants) (A) with respect to filings made with the Commission, (B) with respect to filings required to be made with any Trading Market on which the
Common Stock is then listed for trading, and (C) in compliance with applicable state securities or Blue Sky laws reasonably agreed to by the Company in writing (including, without limitation, fees and disbursements of counsel for the Company in
connection with Blue Sky qualifications or exemptions of the Registrable Securities), (ii) printing expenses (including, without limitation, expenses of printing certificates for Registrable Securities and of printing prospectuses if the printing of
prospectuses is reasonably requested by the Holders of a majority of the Registrable Securities included in the Registration Statement), (iii) messenger, telephone and delivery expenses, (iv) fees and disbursements of counsel for the Company,
(v) Securities Act liability insurance, if the Company so desires such insurance, and (vi) fees and expenses of all other Persons retained by the Company in connection with the consummation of the transactions contemplated by this
Agreement. In addition, the Company shall be responsible for all of its internal expenses incurred in connection with the consummation of the transactions contemplated by this Agreement (including, without limitation, all salaries and expenses of
its officers and employees performing legal or accounting duties), the expense of any annual audit and the fees and expenses incurred in connection with the listing of the Registrable Securities on any securities exchange as required hereunder. In
no event shall the Company be responsible for any broker or similar commissions of any Holder or, except to the extent provided for in the Transaction Documents, any legal fees or other costs of the Holders. 

5. Indemnification. 
 (a)
Indemnification by the Company. The Company shall, notwithstanding any termination of this Agreement, indemnify and hold harmless each Holder, the officers, directors, members, partners, agents, brokers (and any other Persons with a
functionally equivalent role of a Person holding such titles, notwithstanding a lack of such title or any other title) of each of them, each Person who controls any such Holder (within the meaning of Section 15 of the Securities Act or
Section 20 of the Exchange Act) and the officers, directors, members, stockholders, partners, agents and employees (and any other Persons with a functionally equivalent role of a Person holding such titles, notwithstanding a lack of such title
or any other title) of each such controlling Person, to the fullest extent permitted by applicable law, from and against any and all losses, claims, damages, liabilities, costs (including, without limitation, reasonable attorneys’ fees) and
expenses (collectively, “Losses”), as incurred, arising out of or relating to (1) any untrue or alleged untrue statement of a material fact contained in a Registration Statement, any Prospectus or any form of prospectus or in
any amendment or supplement thereto or in any preliminary prospectus, or arising out of or relating to any omission or alleged omission of a material fact required to be stated therein or necessary to make the statements therein (in the case of any
Prospectus or supplement thereto, in light of the circumstances under which they were made) not misleading or (2) any violation or alleged violation by the Company of the Securities Act, the Exchange Act or any state securities law, or any rule
or regulation thereunder, in connection with the performance of its obligations under this Agreement, except to the extent, but only to the extent, that (i) such untrue statements or omissions are based solely upon information regarding such
Holder furnished in writing to the Company by such Holder expressly for use therein, or to the extent that such information relates to such Holder or such Holder’s proposed method of distribution of Registrable Securities and was reviewed and
expressly approved in writing by such Holder expressly for use in a Registration Statement, such Prospectus or in any amendment or supplement thereto (it being understood that the Holder has approved Annex A hereto for this purpose) or
(ii) in the case of an occurrence of an event of the type specified in Section 3(d)(iii)-(vi), the use by such Holder of an outdated, defective or otherwise unavailable Prospectus after the Company has notified such Holder in writing that
the Prospectus is outdated, defective or otherwise unavailable for use by such Holder and prior to the receipt by such 

  
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Holder of the Advice contemplated in Section 6(d). The Company shall notify the Holders promptly of the institution, threat or assertion of any Proceeding arising from or in connection with
the transactions contemplated by this Agreement of which the Company is aware. Such indemnity shall remain in full force and effect regardless of any investigation made by or on behalf of such indemnified person and shall survive the transfer of any
Registrable Securities by any of the Holders in accordance with Section 6(h). 
 (b) Indemnification by Holders. Each Holder
shall, severally and not jointly, indemnify and hold harmless the Company, its directors, officers, agents and employees (and any other Persons with a functionally equivalent role of a Person holding such titles, notwithstanding a lack of such title
or any other title), each Person who controls the Company (within the meaning of Section 15 of the Securities Act and Section 20 of the Exchange Act), and the directors, officers, agents or employees (and any other Persons with a
functionally equivalent role of a Person holding such titles, notwithstanding a lack of such title or any other title) of such controlling Persons, to the fullest extent permitted by applicable law, from and against all Losses, as incurred, to the
extent arising out of or based solely upon any untrue or alleged untrue statement of a material fact contained in any Registration Statement, any Prospectus, or in any amendment or supplement thereto or in any preliminary prospectus, or arising out
of or relating to any omission or alleged omission of a material fact required to be stated therein or necessary to make the statements therein (in the case of any Prospectus or supplement thereto, in light of the circumstances under which they were
made) not misleading (i) to the extent, but only to the extent, that such untrue statement or omission is contained in any information so furnished in writing by such Holder to the Company expressly for inclusion in such Registration Statement
or such Prospectus or (ii) to the extent, but only to the extent, that such information relates to such Holder’s information provided in the Selling Stockholder Questionnaire or the proposed method of distribution of Registrable Securities
and was reviewed and expressly approved in writing by such Holder expressly for use in a Registration Statement (it being understood that the Holder has approved Annex A hereto for this purpose), such Prospectus or in any amendment or
supplement thereto. In no event shall the liability of a selling Holder be greater in amount than the dollar amount of the proceeds (net of all expenses paid by such Holder in connection with any claim relating to this Section 5 and the amount
of any damages such Holder has otherwise been required to pay by reason of such untrue statement or omission) received by such Holder upon the sale of the Registrable Securities included in the Registration Statement giving rise to such
indemnification obligation. 
 (c) Conduct of Indemnification Proceedings. If any Proceeding shall be brought or asserted against any
Person entitled to indemnity hereunder (an “Indemnified Party”), such Indemnified Party shall promptly notify the Person from whom indemnity is sought (the “Indemnifying Party”) in writing, and the Indemnifying
Party shall have the right to assume the defense thereof, including the employment of counsel reasonably satisfactory to the Indemnified Party and the payment of all fees and expenses incurred in connection with defense thereof, provided that the
failure of any Indemnified Party to give such notice shall not relieve the Indemnifying Party of its obligations or liabilities pursuant to this Agreement, except (and only) to the extent that it shall be finally determined by a court of competent
jurisdiction (which determination is not subject to appeal or further review) that such failure shall have materially and adversely prejudiced the Indemnifying Party. 

An Indemnified Party shall have the right to employ separate counsel in any such Proceeding and to participate in the defense thereof, but the
fees and expenses of such counsel shall be at the expense of such Indemnified Party or Parties unless: (1) the Indemnifying Party has agreed in writing to pay such fees and expenses, (2) the Indemnifying Party shall have failed promptly to
assume the defense of such Proceeding and to employ counsel reasonably satisfactory to such Indemnified Party in any such Proceeding, or (3) the named parties to any such Proceeding (including any impleaded parties) include both such
Indemnified Party and the Indemnifying Party, and counsel to the Indemnified Party shall reasonably believe that a material conflict of interest is likely to exist if the same counsel were to represent such Indemnified Party and the Indemnifying
Party (in which case, if such Indemnified Party notifies the Indemnifying Party in writing that it elects to employ separate counsel at the expense of the Indemnifying Party, the Indemnifying Party shall not have the right to assume the defense
thereof and the reasonable fees and expenses of no more than one separate counsel (plus local counsel) shall be at the expense of the Indemnifying Party). The Indemnifying Party shall not be liable for any settlement of any such Proceeding effected
without its written consent, which consent shall not be unreasonably withheld or delayed. No Indemnifying Party shall, without the prior written consent of the Indemnified Party, effect any settlement of any pending Proceeding in respect of which
any Indemnified Party is a party, unless such settlement includes an unconditional release of such Indemnified Party from all liability on claims that are the subject matter of such Proceeding on terms reasonably satisfactory to such Indemnified
Person and does not include any admission as to fault, culpability or failure to act on the part of such Indemnified Person. 

  
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 Subject to the terms of this Agreement, all reasonable fees and expenses of the Indemnified
Party (including reasonable fees and expenses to the extent incurred in connection with investigating or preparing to defend such Proceeding in a manner not inconsistent with this Section) shall be paid to the Indemnified Party, as incurred, within
ten Trading Days of written notice thereof to the Indemnifying Party, provided that the Indemnified Party shall promptly reimburse the Indemnifying Party for that portion of such fees and expenses applicable to such actions for which such
Indemnified Party is finally determined by a court of competent jurisdiction (which determination is not subject to appeal or further review) not to be entitled to indemnification hereunder. The failure to deliver written notice to the Indemnifying
Party within a reasonable time of the commencement of any such action shall not relieve such Indemnifying Party of any liability to the Indemnified Party under this Section 5, except to the extent that the Indemnifying Party is materially and
adversely prejudiced in its ability to defend such action. 
 (d) Contribution. If the indemnification under Section 5(a) or
5(b) is unavailable to an Indemnified Party or insufficient to hold an Indemnified Party harmless for any Losses, then each Indemnifying Party shall contribute to the amount paid or payable by such Indemnified Party, in such proportion as is
appropriate to reflect the relative fault of the Indemnifying Party and Indemnified Party in connection with the actions, statements or omissions that resulted in such Losses as well as any other relevant equitable considerations. The relative fault
of such Indemnifying Party and Indemnified Party shall be determined by reference to, among other things, whether any action in question, including any untrue or alleged untrue statement of a material fact or omission or alleged omission of a
material fact, has been taken or made by, or relates to information supplied by, such Indemnifying Party or Indemnified Party, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such action,
statement or omission. The amount paid or payable by a party as a result of any Losses shall be deemed to include, subject to the limitations set forth in this Agreement, any reasonable attorneys’ or other fees or expenses incurred by such
party in connection with any Proceeding to the extent such party would have been indemnified for such fees or expenses if the indemnification provided for in this Section was available to such party in accordance with its terms. 

The parties hereto agree that it would not be just and equitable if contribution pursuant to this Section 5(d) were determined by pro
rata allocation or by any other method of allocation that does not take into account the equitable considerations referred to in the immediately preceding paragraph. In no event shall the contribution obligation of a Holder of Registrable Securities
be greater in amount than the dollar amount of the proceeds (net of all expenses paid by such Holder in connection with any claim relating to this Section 5 and the amount of any damages such Holder has otherwise been required to pay by reason
of such untrue or alleged untrue statement or omission or alleged omission) received by it upon the sale of the Registrable Securities giving rise to such contribution obligation. 

The indemnity and contribution agreements contained in this Section are in addition to any liability that the Indemnifying Parties may have to
the Indemnified Parties and are not in diminution or limitation of the indemnification provisions under the Purchase Agreement. 
 6. Miscellaneous.

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

(b) No Piggyback on Registrations; Prohibition on Filing Other Registration Statements. Except as set forth on Schedule 6(b), neither
the Company nor any of its security holders (other than the Holders in such capacity pursuant hereto) may include securities of the Company in any Registration Statements other than the Registrable Securities. Except as set forth on Schedule 6(b),
the Company shall not file any other registration statements until all Registrable Securities are registered pursuant to a Registration Statement that is declared effective by the 

  
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Commission, provided that this Section 6(b) (i) shall not prohibit the Company from filing amendments to registration statements filed prior to the date of this Agreement,
(ii) shall not prohibit the Company from filing a shelf registration statement on Form S-3 for a primary offering by the Company, provided that the Company makes no offering of securities pursuant to such
shelf registration statement prior to the effective date of the Registration Statement required hereunder that includes all of the Registrable Securities, and (iii) shall not prohibit the Company from filing one or more of the registration
statements on Form S-8 for the registration of the shares underlying its equity incentive plans. 

(c) Compliance. Each Holder covenants and agrees that it will comply with the prospectus delivery requirements of the Securities Act as
applicable to it (unless an exemption therefrom is available) in connection with sales of Registrable Securities pursuant to a Registration Statement. 

(d) Discontinued Disposition. By its acquisition of Registrable Securities, each Holder agrees that, upon receipt of a notice from the
Company of the occurrence of any event of the kind described in Section 3(d)(iii) through (vi), such Holder will forthwith discontinue disposition of such Registrable Securities under a Registration Statement until it is advised in writing (the
“Advice”) by the Company that the use of the applicable Prospectus (as it may have been supplemented or amended) may be resumed; provided, however, that neither the foregoing nor anything else contained herein shall be deemed to
prohibit or require a Holder to discontinue the settlement of any sale of Registrable Securities with respect to which such Holder has entered into a contract for sale prior to such Holder’s receipt of a notice from the Company of the happening
of any event of the kind described in Section 3(d)(iii) through (vi). The Company will use its best efforts to ensure that the use of the Prospectus may be resumed as promptly as is practicable. The Company agrees and acknowledges that any
periods during which the Holder is required to discontinue the disposition of the Registrable Securities hereunder shall be subject to the provisions of Section 2(d). 

(e) Amendments and Waivers. The provisions of this Agreement, including the provisions of this sentence, may not be amended, modified
or supplemented, and waivers or consents to departures from the provisions hereof may not be given, unless the same shall be in writing and signed by the Company and the Holders of 50.1% or more of the then outstanding Registrable Securities (for
purposes of clarification, this includes any Registrable Securities issuable upon exercise or conversion of any Security); provided that, if any amendment, modification or waiver disproportionately and adversely impacts a Holder (or group of
Holders), the consent of such disproportionately impacted Holder (or group of Holders) shall be required. If a Registration Statement does not register all of the Registrable Securities pursuant to a waiver or amendment done in compliance with the
previous sentence, then the number of Registrable Securities to be registered for each Holder shall be reduced pro rata among all Holders and each Holder shall have the right to designate which of its Registrable Securities shall be omitted from
such Registration Statement. Notwithstanding the foregoing, a waiver or consent to depart from the provisions hereof with respect to a matter that relates exclusively to the rights of a Holder or some Holders and that does not directly or indirectly
affect the rights of other Holders may be given only by such Holder or Holders of all of the Registrable Securities to which such waiver or consent relates; provided, however, that the provisions of this sentence may not be amended,
modified, or supplemented except in accordance with the provisions of the first sentence of this Section 6(e). No consideration shall be offered or paid to any Person to amend or consent to a waiver or modification of any provision of this
Agreement unless the same consideration also is offered to all of the parties to this Agreement. 
 (f) Notices. Any and all notices
or other communications or deliveries required or permitted to be provided hereunder shall be delivered as set forth in the Purchase Agreement. 

(g) Successors and Assigns. This Agreement shall inure to the benefit of and be binding upon the successors and permitted assigns of
each of the parties and shall inure to the benefit of each Holder. The Company may not assign (except by merger) its rights or obligations hereunder without the prior written consent of all of the Holders of the then outstanding Registrable
Securities. Each Holder may assign their respective rights hereunder in the manner and to the Persons as permitted under Section 5.7 of the Purchase Agreement. 

(h) No Inconsistent Agreements. Neither the Company nor any of its Subsidiaries has entered, as of the date hereof, nor shall the
Company or any of its Subsidiaries, on or after the date of this Agreement, enter into any agreement with respect to its securities, that would have the effect of impairing the rights granted to the Holders in this Agreement or otherwise conflicts
with the provisions hereof. Except as set forth on Schedule 6(h), neither the Company nor any of its Subsidiaries has previously entered into any agreement granting any registration rights with respect to any of its securities to any Person that
have not been satisfied in full. 
  

  
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 (i) Execution and Counterparts. This Agreement may be executed in two or more
counterparts, all of which when taken together shall be considered one and the same agreement and shall become effective when counterparts have been signed by each party and delivered to the other party, it being understood that both parties need
not sign the same counterpart. In the event that any signature is delivered by facsimile transmission or by e-mail delivery of a “.pdf” format data file, such signature shall create a valid and
binding obligation of the party executing (or on whose behalf such signature is executed) with the same force and effect as if such facsimile or “.pdf” signature page were an original thereof. 

(j) Governing Law. All questions concerning the construction, validity, enforcement and interpretation of this Agreement shall be
determined in accordance with the provisions of the Purchase Agreement. 
 (k) Cumulative Remedies. The remedies provided herein are
cumulative and not exclusive of any other remedies provided by law. 
 (l) Severability. If any term, provision, covenant or
restriction of this Agreement is held by a court of competent jurisdiction to be invalid, illegal, void or unenforceable, the remainder of the terms, provisions, covenants and restrictions set forth herein shall remain in full force and effect and
shall in no way be affected, impaired or invalidated, and the parties hereto shall use their commercially reasonable efforts to find and employ an alternative means to achieve the same or substantially the same result as that contemplated by such
term, provision, covenant or restriction. It is hereby stipulated and declared to be the intention of the parties that they would have executed the remaining terms, provisions, covenants and restrictions without including any of such that may be
hereafter declared invalid, illegal, void or unenforceable. 
 (m) Headings. The headings in this Agreement are for convenience only,
do not constitute a part of the Agreement and shall not be deemed to limit or affect any of the provisions hereof. 
 (n) Independent
Nature of Holders’ Obligations and Rights. The obligations of each Holder hereunder are several and not joint with the obligations of any other Holder hereunder, and no Holder shall be responsible in any way for the performance of the
obligations of any other Holder hereunder. Nothing contained herein or in any other agreement or document delivered at any closing, and no action taken by any Holder pursuant hereto or thereto, shall be deemed to constitute the Holders as a
partnership, an association, a joint venture or any other kind of group or entity, or create a presumption that the Holders are in any way acting in concert or as a group or entity with respect to such obligations or the transactions contemplated by
this Agreement or any other matters, and the Company acknowledges that the Holders are not acting in concert or as a group, and the Company shall not assert any such claim, with respect to such obligations or transactions. Each Holder shall be
entitled to protect and enforce its rights, including without limitation the rights arising out of this Agreement, and it shall not be necessary for any other Holder to be joined as an additional party in any proceeding for such purpose. The use of
a single agreement with respect to the obligations of the Company contained was solely in the control of the Company, not the action or decision of any Holder, and was done solely for the convenience of the Company and not because it was required or
requested to do so by any Holder. It is expressly understood and agreed that each provision contained in this Agreement is between the Company and a Holder, solely, and not between the Company and the Holders collectively and not between and among
Holders. 
 ******************** 

[Signature pages follow] 

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

			
	VIGIL NEUROSCIENCE, INC.
		
	 By:
	 	 /s/ Ivana
Magovčević-Liebisch



 
			
	 Name:
	 	 Ivana Magovčević-Liebisch

	 Title:
	 	 President and Chief Executive Officer



 [Signature pages of Holders follows.] 

  
 [Signature page of
Holder to VIGIL RRA] 













	
	 Name of Holder: __________________________

	
	 Signature of Authorized Signatory of Holder: __________________________

	
	 Name of Authorized Signatory: _________________________

	
	 Title of Authorized Signatory: __________________________


 [Signature pages continue.] 

  
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