Exhibit 4.20

THIS WARRANT SHALL BE VOID IF NOT EXERCISED PRIOR TO THE EXPIRATION OF THE EXERCISE Series C Warrant Certffcater WARRANTS NUMBER PERIOD PROVIDED FOR IN THE WARRANT AGREEMENT DESCRIBED BELOW INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE C A P N I ACUSIP 14066L 13 9 SEE REVERSE FOR CERTAIN DEFINITION Swarrant(s) (the “Warrants” and each, a “Warrant”) to purchase shares of Common Stock, no par value (“Common Stock”), of Capnia, Inc., a Delaware corporation (the “Company”). Each Warrant entitles the holder, upon exercise during the period set forth in the Warrant Agreement referred to below, to receive from the Company that number of fully paid and non assessable shares of Common Stock as set forth below, at the exercise price (the “Exercise Price”) as determined pursuant to the Warrant Agreement, payable in lawful money (or through “cashless exercise” as provided for in the Warrant Agreement) of the United States of America upon surrender of this Warrant Certificate and payment of the Exercise Price at the office or agency of the Warrant Agent referred to below, subject to the conditions set forth herein and in the Warrant Agreement. Defined terms used in this Warrant Certificate but not defined herein shall have the meanings given to them in the Warrant Agreement (as defined on the reverse hereof). Each Warrant is initially exercisable for one fully paid and non-assessable share of Common Stock. The number of the shares of Common Stock issuable upon exercise of the Warrants is subject to adjustment upon the occurrence of certain events set forth in the Warrant Agreement. JEll The initial Exercise Price per share of Common Stock for any Warrant is equal to $6.25 per share. The Exercise Price is subject to adjustment upon the occurrence of certain events set forth in the Warrant Agreement. Subject to the conditions set forth in the Warrant Agreement, the Warrants may be exercised only during the Exercise Period and to the extent not exercised by the end of such Exercise Period, 3-4-2020, such Warrants shall become void. Reference is hereby made to the further provisions of this Warrant Certificate set forth on the reverse hereof and such further provisions shall for all purposes have the same effect as though fully set forth at this place. This Warrant Certificate shall not be valid unless countersigned by the Warrant Agent, as such term is used in the Warrant Agreement. This Warrant Certificate shall be governed by and construed in accordance with the internal laws of the State of New York, without regard to conflicts of laws principles thereof. COUNTERSIGNED AND REGISTERED: Dated: american stock transfer & trust company, llc (NEW YORK, NY) WARRANT AGENT BY: authorized SIGNATURE PRESIDENT SECRETARY

The Warrants evidenced by this Warrant Certificate are part of a duly authorized issue of Warrants entitling the holder on exercise to receive shares of Common Stock and are issued or to be issued pursuant to a Warrant Agreement dated as of 3-4-2015, (the “ Warrant Agreement “), duly executed and delivered by the Company to American Stock Transfer & Trust Company, LLC, as warrant agent (the “ Warrant Agent “), which Warrant Agreement is hereby incorporated by reference in and made a part of this instrument and is hereby referred to for a description of the rights, limitation of rights, obligations, duties and immunities there under of the Warrant Agent, the Company and the holders (the words “ holders “ or “ holder “ meaning the Registered Holders or Registered Holder) of the Warrants. A copy of the Warrant Agreement may be obtained by the holder hereof upon written request to the Company. Defined terms used in this Warrant Certificate but not defined herein shall have the meanings given to them in the Warrant Agreement. Warrants may be exercised at any time during the Exercise Period set forth in Section 3.3 of the Warrant Agreement. Notwithstanding anything else in this Warrant Certificate or the Warrant Agreement, no Warrant may be exercised unless at the time of exercise (i) a registration statement covering the shares of Common Stock to be issued upon exercise is effective under the Securities Act and (ii) a prospectus the reunder relating to the shares of Common Stock is current, except through “cashless exercise “ as provided for in the Warrant Agreement. The Warrant Agreement provides that upon the occurrence of certain events the number of shares of Common Stock issuable upon exercise of the Warrants set forth on the face hereof may, subject to certain conditions, be adjusted. If, upon exercise of a Warrant, the holder thereof would be entitled to receive a fractional interest in a share of Common Stock, the Company shall, upon exercise, round up to the nearest whole number of shares of Common Stock to be issued to the holder of the Warrant. Warrant Certificates, when surrendered at the principal corporate trust office of the Warrant Agent by the Registered Holder thereof in person or by legal representative or attorney duly authorized in writing, may be exchanged, in the manner and subject to the limitations provided in the Warrant Agreement, but without payment of any service charge, for another Warrant Certificate or Warrant Certificates of like tenor evidencing in the aggregate a like number of Warrants. Upon due presentation for registration of transfer of this Warrant Certificate at the office of the Warrant Agent a new Warrant Certificate or Warrant Certificates of like tenor and evidencing in the aggregate a like number of Warrants shall be issued to the transferee(s) in exchange for this Warrant Certificate, subject to the limitations provided in the Warrant Agreement, without charge except for any tax or other governmental charge imposed in connection therewith. The Company and the Warrant Agent may deem and treat the Registered Holder(s) hereof as the absolute owner(s) of this Warrant Certificate (notwithstanding any notation of ownership or other writing hereon made by anyone), for the purpose of any exercise hereof, of any distribution to the holder(s) hereof, and for all other purposes, and neither the Company nor the Warrant Agent shall be affected by any notice to the contrary. Neither the Warrants nor this Warrant Certificate entitles any holder hereof to any rights of a stockholder of the Company. Election to Purchase (To Be Executed Upon Exercise of Warrant) The undersigned hereby irrevocably elects to exercise the right, represented by this Warrant Certificate, to receive shares of Common Stock and herewith tenders payment for such shares to the order of Capnia, Inc. (the “ Company “) in the amount of $ in accordance with the terms hereof. The undersigned requests that a certificate for such shares be registered in the name of , whose address is and that such shares be delivered to whose address is . If said number of shares is less than all of the shares of Common Stock purchasable hereunder, the undersigned requests that a new Warrant Certificate representing the remaining balance of such shares be registered in the name of , whose address is , and that such Warrant Certificate be delivered to , whose address is . In the event that the Warrant is to be exercised on a “cashless” basis pursuant to Section 3.3.2 of the Warrant Agreement, the number of shares that this Warrant is exercisable for shall be determined in accordance with Section 3.3.2 of the Warrant Agreement. a “Cash Exercise” with respect to Warrant Shares; and/or a “Cashless Exercise” with respect to Warrant Shares, resulting in a delivery obligation by the Company to the Holder of shares of Common Stock representing the applicable Net Number and, if applicable, Market Price Net Number, subject to adjustment. In the event that the Warrant may be exercised, to the extent allowed by the Warrant Agreement, through cashless exercise (i) the number of shares that this Warrant is exercisable for would be determined in accordance with the relevant section of the Warrant Agreement which allows for such cashless exercise and (ii) the holder hereof shall complete the following: The undersigned hereby irrevocably elects to exercise the right, represented by this Warrant Certificate, through the cashless exercise provisions of the Warrant Agreement, to receive shares of Common Stock. If said number of shares is less than all of the shares of Common Stock purchasable hereunder (after giving effect to the cashless exercise), the undersigned requests that a new Warrant Certificate representing the remaining balance of such shares be registered in the name of , whose address is , and that such Warrant Certificate be delivered to , whose address is . whose address is Signature: Tax Identification Number: Date: ASSIGNMENT (To assign the foregoing Warrant, execute this form and supply required information. Do not use this form to purchase shares. Assignment of the Warrant is subject to applicable law.) FOR VALUE RECEIVED, the foregoing Warrant and all rights evidenced thereby are hereby assigned to: Name Address Signed: By: Title: Date: NOTE: The assignor on this Assignment Form must correspond with the name as it appears on the face of the Warrant, without alteration or enlargement or any change whatever. Officers of corporations and those acting in a fiduciary or other representative capacity should provide proper evidence of authority to assign the foregoing Warrant. Signature(s) Guaranteed: By THE Signature) SHOULD BE Guaranteed BY AN eligible Guarantor INSTITUTION, (BANKS, STOCKBROKERS. savings and loan associations and credit unions with membership in an approved signature GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE 17Ad-15.