Exhibit 5.1

Reed Smith LLP

Reed Smith Centre

225 Fifth Avenue

Pittsburgh, PA 15222-2716

+1 412 288 3131

Fax +1 412 288 3063

reedsmith.com

May 1, 2012

iGATE Corporation

6528 Kaiser Drive

Fremont, CA 94555

Ladies and Gentlemen:

We have examined the Registration Statement on Form S-3, File No. 333-170042 (the “Registration Statement”), of iGATE Corporation, a Pennsylvania corporation (the “Company”), filed with the Securities and Exchange Commission (the “Commission”) pursuant to the Securities Act of 1933, as amended (the “Securities Act”), in connection with the offering by the selling stockholders identified in the Registration Statement of up to 6,000,000 shares of the Company’s common stock, par value $0.01 per share (the “Offered Shares”).

We have examined the originals, or photostatic or certified copies, of such records of the Company and certificates of officers of the Company and of public officials and such other documents as we have deemed relevant and necessary as the basis for the opinions set forth below. In our examination, we have assumed the genuineness of all signatures, the legal capacity and competency of all natural persons, the authenticity of all documents submitted to us as originals and the conformity to original documents of all documents submitted to us as copies.

In rendering the foregoing opinion, we have not examined the laws of any jurisdiction other than the laws of the Commonwealth of Pennsylvania and federal laws of the United States of America and the foregoing opinion is limited to such laws. We are not rendering any opinion as to compliance with any antifraud law, rule or regulation relating to securities, or to the sale or issuance thereof.

On the basis of the foregoing and in reliance thereon, we are of the opinion that the Offered Shares are validly issued, fully paid and non-assessable.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the use of our name under the caption “Legal Matters” in the Registration Statement and the prospectus and prospectus supplements that form a part thereof. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the Rules and Regulations of the Commission.