[Signature page follows.] [Signature page to Letter Agreement]

November 18, 2013

VantagePoint Venture Partners IV (Q), L.P.

1001 Bayhill Drive, Suite 300

San Bruno, CA 94066

Edison Venture Fund IV SBIC, L.P.

1009 Lenox Drive #4

Lawrenceville, NJ 08648

Mark E. Galant

Re:    Amendment to Investor Rights Agreement

Ladies and Gentlemen:

Reference is made to that certain Amended and Restated Investor Rights Agreement, dated as of January 11, 2008, by and among GAIN Capital Holdings, Inc. (the “Company”), each person identified on Schedule A thereto as an investor and the person identified on Schedule A thereto as a founding stockholder (the “Agreement”). All capitalized terms used herein and not otherwise defined shall have the meanings given them in the Agreement.

The undersigned, being the (i) the Investors holding a majority of the outstanding shares of voting capital stock of the Company held by the Investors and (ii) the holders of a majority of the shares of voting capital stock held by the Founding Stockholder, do hereby agree with the Company that the right of first refusal set forth in Section 4 of the Agreement is hereby terminated in its entirety and shall be of no further force and effect.

This letter agreement may be executed and delivered in counterparts (including by facsimile transmission and by electronic messaging system), each of which will be deemed an original.

GAIN CAPITAL HOLDINGS, INC

By: /s/ Diego Rotsztain            

Name:     Diego Rotsztain            

Title: EVP, General Counsel        

Accepted and agreed

FOUNDING STOCKHOLDER:

Mark E. Galant

INVESTORS:

VANTAGEPOINT VENTURE PARTNERS IV (Q), L.P.

VANTAGEPOINT VENTURE PARTNERS IV, L.P.

VANTAGEPOINT VENTURE PARTNERS IV

VP NEW YORK VENTURE PARTNERS, L.P.

By: /s/ Alan E. Salzman            

Name: Alan E. Salzman            

Title: Managing Member        

EDISON VENTURE FUND IV SBIC, L.P.

By: /s/ Ross Martinson            

Name: Ross Martinson            

Title: Member of the General Partner