Exhibit 5.1

650 Page Mill Road Palo Alto, CA 94304-1050 PHONE 650.493.9300 FAX 650.493.6811 www.wsgr.com

May 12, 2014

SVB Financial Group

3003 Tasman Drive

Santa Clara, CA 95054

Re: Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as counsel to SVB Financial Group, a Delaware corporation (the “Company”), in connection with the filing by the Company with the Securities and Exchange Commission (the “Commission”) of a registration statement on Form S-3 (the “Registration Statement”), under the Securities Act of 1933, as amended (the “Act”), that is automatically effective under the Act pursuant to Rule 462(e) promulgated thereunder. Pursuant to the Registration Statement, the Company is registering under the Act an indeterminate number of shares of the Company’s common stock, $0.001 par value per share (the “Common Stock”). The shares of Common Stock are to be sold from time to time as set forth in the Registration Statement, the prospectus contained therein (the “Prospectus”) and any supplements to the Prospectus (the “Prospectus Supplements”).

The shares of Common Stock are to be sold pursuant to an underwriting agreement approved by the Board of Directors of the Company or a duly constituted and acting committee thereof (the Board of Directors or such committee being hereinafter referred to as the “Board”) in substantially the form to be filed under a Current Report on Form 8-K (the “Underwriting Agreement”). The number of shares of Common Stock to be issued and sold will be set forth in a final Prospectus or Prospectus Supplement.

We have examined the Registration Statement and such other instruments, documents, certificates and records that we have deemed relevant and necessary for the basis of our opinions hereinafter expressed. In such examination, we have assumed: (i) the authenticity of original documents and the genuineness of all signatures; (ii) the conformity to the originals of all documents submitted to us as copies; (iii) the truth, accuracy and completeness of the information, representations and warranties contained in the instruments, documents, certificates and records we have reviewed; (iv) that the Registration Statement, and any amendments thereto (including post-effective amendments), will have become effective under the Act; (v) that a Prospectus or Prospectus Supplement will have been filed with the Commission describing the shares of Common Stock offered thereby; (vi) that the shares of Common Stock will be issued and sold in compliance with applicable U.S. federal and state securities laws and in the manner stated in the Registration Statement and applicable Prospectus or Prospectus Supplement; (vii) that a definitive underwriting agreement with respect to any shares of Common Stock offered will have been duly authorized and validly executed and delivered by the Company and the other parties thereto; (viii) with respect to shares of Common Stock, that there will be sufficient shares of Common Stock authorized under the Company’s organizational documents that are not otherwise reserved for issuance; and (ix) the legal capacity of all natural persons. As to any facts material to the opinions expressed herein that were not independently established or verified, we have relied upon oral or written statements and representations of officers and other representatives of the Company.

Based on such examination, we are of the opinion that when both: (i) the Board has taken all necessary corporate action to approve the issuance and the terms of the offering of the shares of Common Stock and related

AUSTIN    BEIJING    BRUSSELS    GEORGETOWN, DE    HONG KONG    LOS ANGELES    NEW YORK

PALO ALTO    SAN DIEGO    SAN FRANCISCO    SEATTLE    SHANGHAI    WASHINGTON, DC

SVB Financial Group

May 12, 2014

Page 2

matters and (ii) the shares of Common Stock have been duly issued and delivered against payment therefor in accordance with the Underwriting Agreement approved by the Board, the shares of Common Stock will be validly issued, fully paid and nonassessable.

Our opinion that any document is legal, valid and binding is qualified as to:

(i) limitations imposed by bankruptcy, insolvency, reorganization, arrangement, fraudulent conveyance, moratorium or other laws relating to or affecting the rights of creditors generally;

(ii) rights to indemnification and contribution, which may be limited by applicable law or equitable principles; and

(iii) general principles of equity, including without limitation concepts of materiality, reasonableness, good faith and fair dealing, and the possible unavailability of specific performance or injunctive relief and limitation of rights of acceleration, regardless of whether such enforceability is considered in a proceeding in equity or at law.

We express no opinion herein as to the laws of any state or jurisdiction other than the General Corporation Law of the State of Delaware (including the statutory provisions and all applicable judicial decisions interpreting those laws) and the federal laws of the United States of America.

We hereby consent to the filing of this opinion as an exhibit to the above-referenced Registration Statement and to the use of our name wherever it appears in the Registration Statement, the Prospectus, any Prospectus Supplement and in any amendment or supplement thereto. In giving such consent, we do not believe that we are “experts” within the meaning of such term as used in the Act or the rules and regulations of the Commission issued thereunder with respect to any part of the Registration Statement, including this opinion as an exhibit or otherwise.

Very truly yours,

WILSON SONSINI GOODRICH & ROSATI

Professional Corporation

/s/ Wilson Sonsini Goodrich & Rosati