TWILIO INC

APPENDIX C

Proposed Amendments to Our Certificate of Incorporation (Proposal No. 6)

The proposed amendments to Articles IV and V of our certificate of incorporation related to Proposal No. 6 are shown below. Additions are indicated by underlining and deletions are indicated by strike-outs.

ARTICLE IV

A. Classes of Stock. The total number of shares of capital stock that the Corporation shall have authority to issue is 1,2100,000,000, consisting of the following: 1,000,000,000 shares of Class A Common Stock, par value $0.001 per share (“Class A Common Stock”),100,000,000 shares of Class B Common Stock, par value $0.001 per share (“Class B Common Stock”), and 100,000,000 shares of undesignated Preferred Stock, par value $0.001 per share (“Preferred Stock”).

Immediately upon the acceptance of this Amended and Restated Certificate of Incorporation for filing by the Secretary of State of the State of Delaware (the “Effective Time”), each share of the Corporation’s capital stock issued and outstanding or held as treasury stock immediately prior to the Effective Time, shall, automatically and without further action by any stockholder, be reclassified as, and shall become, one share of Class B Common Stock.

B. Rights of Preferred Stock. The Board of Directorsof the Corporation (the “Board of Directors”) is authorized, subject to any limitations prescribed by law but to the fullest extent permitted by law, to provide by resolution for the designation and issuance of shares of Preferred Stock in one or more series, and to establish from time to time the number of shares to be included in each such series, and to fix the designation, powers, (which may include, without limitation, full, limited or no voting powers), preferences, and relative, participating, optional or other rights of the shares of each such series and any qualifications, limitations or restrictions thereof, and to file a certificate pursuant to the applicable law of the State of Delaware (such certificate being hereinafter referred to as a “Preferred Stock Designation”), setting forth such resolution or resolutions.

C. Vote to Increase or Decrease Authorized Shares of Preferred Stock. The number of authorized shares of Preferred Stock may be increased or decreased (but not below the number of shares thereof then outstanding) by the affirmative vote of the holders of a majority of the voting power of all of the outstanding shares of capital stock of the Corporation entitled to vote thereon, without a separate class vote of the holders of Preferred Stock, or any separate series votes of any series thereof, unless a vote of any such holders is required pursuant to the terms of any Preferred Stock Designation.

D. Rights of Class A Common Stockand Class B Common Stock. The relative powers, rights, qualifications, limitations and restrictions granted to or imposed on the shares of Class A Common Stock and Class B Common Stock are as follows:

1. Voting Rights.

(a) General Right to Vote Together; Exception. Except as otherwise expressly provided herein or required by applicable law, the holders of Class A Common Stock and Class B Common Stock shall vote together as one class on all matters submitted to a vote of the stockholders; provided, however, s Subject to the terms of any Preferred Stock Designation, the number of authorized shares of Class A Common Stockor Class B Common Stockmay be increased or decreased (but not below the number of shares thereof then outstanding) by the affirmative vote of the holders of a majority of the voting power of the capital stock of the Corporation entitled to vote.

(b) Votes Per Share 2. Except as otherwise expressly provided herein or required by applicable law, on any matter that is submitted to a vote of the stockholders, each holder of Class A Common Stock shall be entitled to one (1) vote for each such share, and each holder of Class B Common Stock shall be entitled to ten (10) votes for each such share.

APPENDIX CProposed Amendments to Our Certificate of Incorporation (Proposal No. 6)

2. Identical Rights. Except as otherwise expressly provided herein or required by applicable law, shares of Class A Common Stock and Class B Common Stock shall have the same rights and privileges and rank equally, share ratably and be identical in all respects as to all matters, including, without limitation:

(a) Dividends and Distributions. Shares of Class A Common Stock and Class B Common Stock shall be treated equally, identically and ratably, on a per share basis, with respect to any Distribution paid or distributed by the Corporation, unless different treatment of the shares of each such class is approved by the affirmative vote of the holders of a majority of the outstanding shares of Class A Common Stock and by the affirmative vote of the holders of a majority of the outstanding shares of Class B Common Stock, each voting separately as a class; provided, however, that in the event a Distribution is paid in the form of Class A Common Stock or Class B Common Stock (or Rights to acquire such stock), then holders of Class A Common Stock shall receive Class A Common Stock (or Rights to acquire such stock, as the case may be) and holders of Class B Common Stock shall receive Class B Common Stock (or Rights to acquire such stock, as the case may be).

(b) Subdivision or Combination. If the Corporation in any manner subdivides or combines the outstanding shares of Class A Common Stock or Class B Common Stock, the outstanding shares of the other such class will be subdivided or combined in the same proportion and manner, unless different treatment of the shares of each such class is approved by the affirmative vote of the holders of a majority of the outstanding shares of Class A Common Stock and by the affirmative vote of the holders of a majority of the outstanding shares of Class B Common Stock, each voting separately as a class.

(c) Equal Treatment in a Change of Control or any Merger Transaction. In connection with any Change of Control Transaction, shares of Class A Common Stock and Class B Common Stock shall be treated equally, identically and ratably, on a per share basis, with respect to any consideration into which such shares are converted or any consideration paid or otherwise distributed to stockholders of the Corporation, unless different treatment of the shares of each such class is approved by the affirmative vote of the holders of a majority of the outstanding shares of Class A Common Stock and by the affirmative vote of the holders of a majority of the outstanding shares of Class B Common Stock, each voting separately as a class. Any merger or consolidation of the Corporation with or into any other entity, which is not a Change of Control Transaction, shall require approval by the affirmative vote of the holders of a majority of the outstanding shares of Class A Common Stock and by the affirmative vote of the holders of a majority of the outstanding shares of Class B Common Stock, each voting separately as a class, unless (i) the shares of Class A Common Stock and Class B Common Stock remain outstanding and no other consideration is received in respect thereof or (ii) such shares are converted on a pro rata basis into shares of the surviving or parent entity in such transaction having identical rights to the shares of Class A Common Stock and Class B Common Stock, respectively.

3. Conversion of Class B Common Stock.

(a) Voluntary Conversion. Each one (1) share of Class B Common Stock shall be convertible into one (1) share of Class A Common Stock at the option of the holder thereof at any time upon written notice to the transfer agent of the Corporation.

(b) Automatic Conversion. Shares of Class B Common Stock shall automatically, without any further action, convert into an equal number of shares of Class A Common Stock upon the earlier of:

(i) a Transfer of such share; provided that no such automatic conversion shall occur in the case of a Transfer by a Class B Stockholder, for tax or estate planning purposes, to any of the persons or entities listed in clauses (A) through (E) below (each, a “Permitted Transferee”) and from any such Permitted Transferee back to such Class B Stockholder and/or any other Permitted Transferee established by or for such Class B Stockholder:

(A) a family member of such Class B Stockholder, which shall include with respect to any natural person who is a Class B Stockholder, the spouse, domestic partner, parents, grandparents, lineal descendants, siblings and lineal descendants of siblings of such Class B Stockholder; and provided, further, that lineal descendants shall include adopted persons, but only so long as they are adopted during minority;

(B) a trust for the benefit of such Class B Stockholder or persons other than the Class B Stockholder so long as the Class B Stockholder and/or family members of such Class B Stockholder have sole dispositive power and exclusive Voting Control with respect to the shares of Class B Common Stock held by such trust; provided such Transfer does not involve any payment of cash, securities, property or other consideration (other

APPENDIX CProposed Amendments to Our Certificate of Incorporation (Proposal No. 6)

than an interest in such trust) to the Class B Stockholder and, provided, further, that in the event such Class B Stockholder and/or family members of such Class B Stockholder no longer have sole dispositive power and exclusive Voting Control with respect to the shares of Class B Common Stock held by such trust, each share of Class B Common Stock then held by such trust shall automatically convert into one (1) fully paid and nonassessable share of Class A Common Stock;

(C) a trust under the terms of which such Class B Stockholder has retained a “qualified interest” within the meaning of §2702(b)(1) of the Internal Revenue Code (or successor provision) and/or a reversionary interest so long as the Class B Stockholder has sole dispositive power and exclusive Voting Control with respect to the shares of Class B Common Stock held by such trust; provided, however, that in the event the Class B Stockholder no longer has sole dispositive power and exclusive Voting Control with respect to the shares of Class B Common Stock held by such trust, each share of Class B Common Stock then held by such trust shall automatically convert into one (1) fully paid and nonassessable share of Class A Common Stock;

(D) an Individual Retirement Account, as defined in Section 408(a) of the Internal Revenue Code (or successor provision), or a pension, profit sharing, stock bonus or other type of plan or trust of which such Class B Stockholder is a participant or beneficiary and which satisfies the requirements for qualification under Section 401 of the Internal Revenue Code; provided that in each case such Class B Stockholder has sole dispositive power and exclusive Voting Control with respect to the shares of Class B Common Stock held in such account, plan or trust, and provided, further, that in the event the Class B Stockholder no longer has sole dispositive power and exclusive Voting Control with respect to the shares of Class B Common Stock held by such account, plan or trust, each share of Class B Common Stock then held by such trust shall automatically convert into one (1) fully paid and nonassessable share of Class A Common Stock;

(E) a corporation, partnership or limited liability company in which such Class B Stockholder directly, or indirectly through one or more Permitted Transferees, owns shares, partnership interests or membership interests, as applicable, with sufficient Voting Control in the corporation, partnership or limited liability company, as applicable, or otherwise has legally enforceable rights, such that the Class B Stockholder and/or family members of such Class B Stockholder retain sole dispositive power and exclusive Voting Control with respect to the shares of Class B Common Stock held by such corporation, partnership or limited liability company; provided, however, that in the event the Class B Stockholder and/or family members of such Class B Stockholder no longer own sufficient shares, partnership interests or membership interests, as applicable, or no longer has sufficient legally enforceable rights to ensure the Class B Stockholder and/or family members of such Class B Stockholder retain sole dispositive power and exclusive Voting Control with respect to the shares of Class B Common Stock held by such corporation, partnership or limited liability company, as applicable, each share of Class B Common Stock then held by such corporation, partnership or limited liability company, as applicable, shall automatically convert into one (1) fully paid and nonassessable share of Class A Common Stock; and

(ii) the date specified by a written notice and certification request of the Corporation to the holder of such share of Class B Common Stock requesting a certification, in a form satisfactory to the Corporation, verifying such holder’s ownership of Class B Common Stock and confirming that a conversion to Class A Common Stock has not occurred, which date shall not be less than sixty (60) calendar days after the date of such notice and certification request; provided that no such automatic conversion pursuant to this subsection (ii) shall occur in the case of a Class B Stockholder or its Permitted Transferees that furnishes a certification satisfactory to the Corporation prior to the specified date.

(c) Conversion Upon Death or Incapacity of a Class B Stockholder.

(i) Each share of Class B Common Stock held of record by a Class B Stockholder who is a natural person, or by such Class B Stockholder’s Permitted Transferees, shall automatically, without any further action, convert into one (1) fully paid and nonassessable share of Class A Common Stock upon the death or Incapacity of such Class B Stockholder.

APPENDIX CProposed Amendments to Our Certificate of Incorporation (Proposal No. 6)

(d) Automatic Conversion of all Outstanding Class B Common Stock. Each one (1) share of Class B Common Stock shall automatically, without any further action, convert into one (1) share of Class A Common Stock upon the date specified by affirmative vote of the holders of at least sixty-six and two-thirds percent (66-2/3%) of the outstanding shares of Class B Common Stock, voting as a single class.

(e) Final Conversion of Class B Common Stock. On the Final Conversion Date, each one (1) outstanding share of Class B Common Stock shall automatically, without any further action, convert into one (1) share of Class A Common Stock. Following such conversion, the reissuance of all shares of Class B Common Stock shall be prohibited, and such shares shall be retired and cancelled in accordance with Section 243 of the DGCL and the filing by the Secretary of State of the State of Delaware required thereby, and upon such retirement and cancellation, all references to Class B Common Stock in this Amended and Restated Certificate of Incorporation shall be eliminated.

(f) Procedures. The Corporation may, from time to time, establish such policies and procedures relating to the conversion of Class B Common Stock to Class A Common Stock and the general administration of this dual class stock structure, including the issuance of stock certificates (or the establishment of book-entry positions) with respect thereto, as it may deem reasonably necessary or advisable, and may from time to time request that holders of shares of Class B Common Stock furnish certifications, affidavits or other proof to the Corporation as it deems necessary to verify the ownership of Class B Common Stock and to confirm that a conversion to Class A Common Stock has not occurred. A determination by the Secretary of the Corporation that a Transfer results in a conversion to Class A Common Stock shall be conclusive and binding.

(g) Immediate Effect. In the event of a conversion of shares of Class B Common Stock to shares of Class A Common Stock pursuant to this Section D.3 or upon the Final Conversion Date, such conversion(s) shall be deemed to have been made at the time that the Transfer of shares occurred or immediately upon the Final Conversion Date, as applicable. Upon any conversion of Class B Common Stock to Class A Common Stock, all rights of the holder of shares of Class B Common Stock shall cease and the person or persons in whose names or names the certificate or certificates (or book-entry position(s)) representing the shares of Class A Common Stock are to be issued shall be treated for all purposes as having become the record holder or holders of such shares of Class A Common Stock. Shares of Class B Common Stock that are converted into shares of Class A Common Stock as provided in this Section D.3 shall be retired and may not be reissued.

(h) Reservation of Stock. The Corporation shall at all times reserve and keep available out of its authorized but unissued shares of Class A Common Stock, solely for the purpose of effecting the conversion of the shares of Class B Common Stock, such number of its shares of Class A Common Stock as shall from time to time be sufficient to effect the conversion of all outstanding shares of Class B Common Stock into shares of Class A Common Stock.

E. No Further Issuances. Except for the issuance of Class B Common Stock issuable upon exercise of Rights outstanding at the Effective Time or a dividend payable in accordance with Article IV, Section D.2(a), the Corporation shall not at any time after the Effective Time issue any additional shares of Class B Common Stock, unless such issuance is approved by the affirmative vote of the holders of a majority of the outstanding shares of Class B Common Stock. After the Final Conversion Date, the Corporation shall not issue any additional shares of Class B Common Stock.

ARTICLE V

The following terms, where capitalized in this Amended and Restated Certificate of Incorporation, shall have the meanings ascribed tothemit in this Article V:

“Effective Time” means 8:03 AM, Eastern Time, on June 28, 2016.

“Change of Control Share Issuance” means the issuance by the Corporation, in a transaction or series of related transactions, of voting securities representing more than two percent (2%) of the total voting power (assuming Class A Common Stock and Class B Common Stock each have one (1) vote per share) of the Corporation before such issuance to any person or persons acting as a group as contemplated in Rule 13d-5(b) under the Exchange Act (or any successor provision) that immediately prior to such transaction or series of related transactions held fifty percent (50%) or less of the total voting power of the Corporation (assuming Class A Common Stock and Class B Common Stock each have one (1) vote per share), such that, immediately following such transaction or series of related transactions, such person or group of persons would hold more than fifty percent (50%) of the total voting power of the Corporation (assuming Class A Common Stock and Class B Common Stock each have one (1) vote per share).

APPENDIX CProposed Amendments to Our Certificate of Incorporation (Proposal No. 6)

“Change of Control Transaction” means (i) the sale, lease, exchange, or other disposition (other than liens and encumbrances created in the ordinary course of business, including liens or encumbrances to secure indebtedness for borrowed money that are approved by the Corporation’s Board of Directors, so long as no foreclosure occurs in respect of any such lien or encumbrance) of all or substantially all of the Corporation’s property and assets (which shall for such purpose include the property and assets of any direct or indirect subsidiary of the Corporation), provided that any sale, lease, exchange or other disposition of property or assets exclusively between or among the Corporation and any direct or indirect subsidiary or subsidiaries of the Corporation shall not be deemed a “Change of Control Transaction”; (ii) the merger, consolidation, business combination, or other similar transaction of the Corporation with any other entity, other than a merger, consolidation, business combination, or other similar transaction that would result in the voting securities of the Corporation outstanding immediately prior thereto continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving entity or its parent) more than fifty percent (50%) of the total voting power represented by the voting securities of the Corporationand more than fifty percent (50%) of the total number of outstanding shares of the Corporation’s capital stock, in each case as outstanding immediately after such merger, consolidation, business combination, or other similar transaction, and the stockholders of the Corporation immediately prior to the merger, consolidation, business combination, or other similar transaction own voting securities of the Corporation, the surviving entity or its parent immediately following the merger, consolidation, business combination, or other similar transaction in substantially the same proportions (vis à vis each other) as such stockholders owned the voting securities of the Corporation immediately prior to the transaction; (iii) a recapitalization, liquidation, dissolution, or other similar transaction involving the Corporation, other than a recapitalization, liquidation, dissolution, or other similar transaction that would result in the voting securities of the Corporation outstanding immediately prior thereto continuing to represent (either by remaining outstanding or being converted into voting securities of the surviving entity or its parent) more than fifty percent (50%) of the total voting power represented by the voting securities of the Corporationand more than fifty percent (50%) of the total number of outstanding shares of the Corporation’s capital stock, in each case as outstanding immediately after such recapitalization, liquidation, dissolution or other similar transaction, and the stockholders of the Corporation immediately prior to the recapitalization, liquidation, dissolution or other similar transaction own voting securities of the Corporation, the surviving entity or its parent immediately following the recapitalization, liquidation, dissolution or other similar transaction in substantially the same proportions (vis a vis each other) as such stockholders owned the voting securities of the Corporation immediately prior to the transaction; and (iv) any Change of Control Share Issuance.

“Class B Stockholder” means (i) the registered holder of a share of Class B Common Stock at the Effective Time and (ii) the registered holder of any shares of Class B Common Stock that are originally issued by the Corporation after the Effective Time.

“Distribution” means (i) any dividend or distribution of cash, property or shares of the Corporation’s capital stock; and (ii) any distribution following or in connection with any liquidation, dissolution or winding up of the Corporation, either voluntary or involuntary.

“Exchange Act” means the United States Securities Exchange Act of 1934, as amended.

“Final Conversion Date” means 5:00 p.m. in New York City, New York on the first Trading Day falling on or after the seventh (7th) year anniversary of the Effective Time.

“Incapacity” shall mean that such holder is incapable of managing his or her financial affairs under the criteria set forth in the applicable probate code that can be expected to result in death or which has lasted or can be expected to last for a continuous period of not less than twelve (12) months as determined by a licensed medical practitioner. In the event of a dispute regarding whether a Class B Stockholder has suffered an Incapacity, no Incapacity of such holder will be deemed to have occurred unless and until an affirmative ruling regarding such Incapacity has been made by a court of competent jurisdiction.

“Rights” means any option, warrant, restricted stock unit, conversion right or contractual right of any kind to acquire shares of the Corporation’s authorized but unissued capital stock.

“Securities Act” means the United States Securities Act of 1933, as amended.

“Securities Exchange” means, at any time, the registered national securities exchange on which the Corporation’s equity securities are then principally listed or traded, which shall be the New York Stock Exchange or NASDAQ Global Market (or similar national quotation system of the NASDAQ Stock Market) (“NASDAQ”) or any successor exchange of either the New York Stock Exchange or NASDAQ.

APPENDIX CProposed Amendments to Our Certificate of Incorporation (Proposal No. 6)

“Trading Day” means any day on which the Securities Exchange is open for trading.

“Transfer” of a share of Class B Common Stock shall mean any sale, assignment, transfer, conveyance, hypothecation or other transfer or disposition of such share or any legal or beneficial interest in such share, whether or not for value and whether voluntary or involuntary or by operation of law. A “Transfer” shall also include, without limitation, (i) a transfer of a share of Class B Common Stock to a broker or other nominee (regardless of whether or not there is a corresponding change in beneficial ownership) or (ii) the transfer of, or entering into a binding agreement with respect to, Voting Control over a share of Class B Common Stock by proxy or otherwise; provided, however, that the following shall not be considered a “Transfer”: (a) the grant of a proxy to officers or directors of the Corporation at the request of the Board of Directors of the Corporation in connection with actions to be taken at an annual or special meeting of stockholders; (b) the pledge of shares of Class B Common Stock by a Class B Stockholder that creates a mere security interest in such shares pursuant to abona fide loan or indebtedness transaction so long as the Class B Stockholder continues to exercise Voting Control over such pledged shares; provided, however, that a foreclosure on such shares of Class B Common Stock or other similar action by the pledge shall constitute a “Transfer”; or (c) the fact that, as of the Effective Time or at any time after the Effective Time, the spouse of any Class B Stockholder possesses or obtains an interest in such holder’s shares of Class B Common Stock arising solely by reason of the application of the community property laws of any jurisdiction, so long as no other event or circumstance shall exist or have occurred that constitutes a “Transfer” of such shares of Class B Common Stock.

“Voting Control” with respect to a share of Class B Common Stock means the exclusive power (whether directly or indirectly) to vote or direct the voting of such share of Class B Common Stock by proxy, voting agreement, or otherwise.