SORRENTO THERAPEUTICS, INC. TRANSFER FEE $25.00

Exhibit 4.1

016570| 003590|127C|RESTRICTED||4|057-423

COMMON STOCK

PAR VALUE $0.0001

COMMON STOCK

THIS CERTIFICATE IS TRANSFERABLE IN CANTON, MA AND NEW YORK, NY

Certificate Number

ZQ 000000

Shares

* * 600620 * * * * * *

* * * 600620 * * * * *

* * * * 600620 * * * *

* * * * * 600620 * * *

* * * * * * 600620 * *

SORRENTO THERAPEUTICS, INC.

INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE

THIS CERTIFIES THAT

MR. SAMPLE & MRS. SAMPLE & MR. SAMPLE & MRS. SAMPLE

CUSIP XXXXXX XX X

SEE REVERSE FOR CERTAIN DEFINITIONS

is the owner of

* * * SIX HUNDRED THOUSAND SIX HUNDRED AND TWENTY* * *

FULLY-PAID AND NON-ASSESSABLE SHARES OF THE COMMON STOCK OF

Sorrento Therapeutics, Inc. (hereinafter called the “Company”), transferable on the books of the Company in person or by duly authorized attorney, upon surrender of this Certificate properly endorsed. This Certificate and the shares represented hereby, are issued and shall be held subject to all of the provisions of the Certificate of Incorporation, as amended, and the Bylaws, as amended, of the Company (copies of which are on file with the Company and with the Transfer Agent), to all of which each holder, by acceptance hereof, assents. This Certificate is not valid unless countersigned and registered by the Transfer Agent and Registrar.

Witness the facsimile seal of the Company and the facsimile signatures of its duly authorized officers.

FACSIMILE SIGNATURE TO COME

Chairman & Chief Executive Officer

FACSIMILE SIGNATURE TO COME

Chief Scientific Officer & Secretary

SORRENTO THERAPEUTICS, INC.

SEAL

2009

DELAWARE

DATED <<Month Day, Year>> COUNTERSIGNED AND REGISTERED:

COMPUTERSHARE TRUST COMPANY, N.A.

TRANSFER AGENT AND REGISTRAR,

By

AUTHORIZED SIGNATURE

1234567

SORRENTO THERAPEUTICS, INC.

PO BOX 43004, Providence, RI ###-###-####

MR A SAMPLE

DESIGNATION (IF ANY)

ADD 1

ADD 2

ADD 3

ADD 4

CUSIP XXXXXX XX X Holder ID XXXXXXXXXX

Insurance Value 1,000,000.00

Number of Shares 123456

DTC 12345678 123456789012345

Certificate Numbers Num/No. Denom. Total

1234567890 ###-###-#### 1 1 1

1234567890 ###-###-#### 2 2 2

1234567890 ###-###-#### 3 3 3

1234567890 ###-###-#### 4 4 4

1234567890 ###-###-#### 5 5 5

1234567890 ###-###-#### 6 6 6

Total Transaction 7

SORRENTO THERAPEUTICS, INC.

TRANSFER FEE $25.00

THE COMPANY WILL FURNISH WITHOUT CHARGE TO EACH SHAREHOLDER WHO SO REQUESTS, A SUMMARY OF THE POWERS, DESIGNATIONS, PREFERENCES AND RELATIVE, PARTICIPATING, OPTIONAL OR OTHER SPECIAL RIGHTS OF EACH CLASS OF STOCK OF THE COMPANY AND THE QUALIFICATIONS, LIMITATIONS OR RESTRICTIONS OF SUCH PREFERENCES AND RIGHTS, AND THE VARIATIONS IN RIGHTS, PREFERENCES AND LIMITATIONS DETERMINED FOR EACH SERIES, WHICH ARE FIXED BY THE ARTICLES OF INCORPORATION OF THE COMPANY, AS AMENDED, AND THE RESOLUTIONS OF THE BOARD OF DIRECTORS OF THE COMPANY, AND THE AUTHORITY OF THE BOARD OF DIRECTORS TO DETERMINE VARIATIONS FOR FUTURE SERIES. SUCH REQUEST MAY BE MADE TO THE OFFICE OF THE SECRETARY OF THE COMPANY OR TO THE TRANSFER AGENT. THE BOARD OF DIRECTORS MAY REQUIRE THE OWNER OF A LOST OR DESTROYED STOCK CERTIFICATE, OR HIS LEGAL REPRESENTATIVES, TO GIVE THE COMPANY A BOND TO INDEMNIFY IT AND ITS TRANSFER AGENTS AND REGISTRARS AGAINST ANY CLAIM THAT MAY BE MADE AGAINST THEM ON ACCOUNT OF THE ALLEGED LOSS OR DESTRUCTION OF ANY SUCH CERTIFICATE.

(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING POSTAL ZIP CODE, OF ASSIGNEE)

of the common stock represented by the within Certificate, and do hereby irrevocably constitute and appoint

to transfer the said stock on the books of the within-named Corporation with full power of substitution in the premises.