UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Schedule 13D

(Rule 13d-101)

Under the Securities Exchange Act of 1934

(Amendment No. 3)

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ¨

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Exchange Act”) or otherwise subject to the liabilities of that section of the Exchange Act but shall be subject to all other provisions of the Exchange Act.

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Pursuant to Rule 13d-2 of the Securities Exchange Act of 1934, this Amendment No. 3 (“Amendment No. 3”) amends and supplements the Schedule 13D filed with the United States Securities and Exchange Commission (the “SEC”) on February 11, 2011 (the “Original 13D”), as amended and supplemented by Amendment No. 1 to the Original 13D filed with the SEC on May 19, 2011 (the “Amendment No. 1”) and Amendment No. 2 to the Original 13D filed with the SEC on December 19, 2011 (the “Amendment No. 2”, and, together with the Original 13D, the Amendment No. 1 and this Amendment No.3, the “Schedule 13D”) with respect to the Items and matters described below. The Schedule 13D was filed jointly on behalf of (i) Viscaria Limited, a private company limited by shares formed under the laws of Cyprus (“Investor”), (ii) Apax Europe VI-A, L.P. and Apax Europe VI-1, L.P. (collectively, the “Apax Europe VI Funds”), (iii) Apax Europe VII-A, L.P., Apax Europe VII-B, L.P. and Apax Europe VII-1, L.P. (collectively, the “Apax Europe VII Funds”), (iv) Apax US VII, L.P. (the “Apax US Fund”), (v) Apax Europe VI GP L.P. Inc. and Apax Europe VI GP Co. Limited (collectively, the “Apax Europe VI Funds GPs”), (vi) Apax Europe VII GP L.P. Inc. and Apax Europe VII GP Co. Limited (collectively, the “Apax Europe VII Funds GPs”), (vii) Apax US VII GP, L.P. and Apax US VII GP, Ltd. (collectively, the “Apax US Fund GPs”), (viii) Apax Partners Europe Managers Ltd, (ix) Apax Guernsey (Holdco) PCC Limited, and (x) John F. Megrue (the entities and persons in clauses (i) through (x), collectively the “Reporting Persons”). Capitalized terms used in this Amendment No. 3 but not otherwise defined herein have the meanings set forth in the Schedule 13D.

Item 3 of the Schedule 13D is supplemented as follows:

The total amount of funds used by Investor to purchase the shares of Common Stock from the Sellers (defined below) pursuant to the Share Transfer (defined below) as described in this Amendment No. 3 to the Schedule 13D was USD $27,150,000, which was obtained from capital contributions of limited partners to the Apax Funds.

Item 4 of the Schedule 13D is supplemented as follows:

On May 1, 2011, Investor, Sunil Wadhwani (“Mr. Wadhwani”) and Ashok Trivedi (“Mr. Trivedi”, and together with Mr. Wadhwani, “Sellers”) entered into a Common Stock Purchase Agreement (the “Common Stock Purchase Agreement”), pursuant to which each Seller agreed to sell 750,000 shares of Common Stock owned by such Seller to Investor for a per share price of $18.10 (the “Share Transfer”). The Share Transfer of the aggregate 1,500,000 shares of Common Stock was effected on May 8, 2012.

The foregoing summary description of the Common Stock Purchase Agreement and the transactions contemplated thereby does not purport to be complete and is subject to and qualified in its entirety by reference to the Common Stock Purchase Agreement, the terms of which are set forth in Exhibit 10 hereto, and the terms of which are incorporated herein by reference.

Each of the Reporting Persons acquired the shares of Common Stock from the Sellers pursuant to the Share Transfer for investment purposes. Consistent with such purposes, the Reporting Persons may engage in communications with, without limitation, management, directors and shareholders (including Reporting Persons) of the Issuer, and may make suggestions concerning the Issuer’s operations, prospects, business and financial strategies, strategic transactions, assets and liabilities, business and financing alternatives and such other matters as the Reporting Persons may deem relevant to their investment in the Common Stock they own.

Each of the Reporting Persons expects to continuously review such person’s investment in the Issuer and, depending on various factors, including but not limited to, the price of shares of Common Stock, the terms and conditions of the transaction, prevailing market conditions and such other considerations as such Reporting Person deems relevant, may at any time or from time to time, and subject to any required regulatory approvals, lend funds, invest in debt or similar investments issued by the Issuer, acquire additional shares of Common Stock, preferred stock of the Issuer or other securities convertible into or exercisable or exchangeable for Common Stock from time to time on the open market, in privately-negotiated transactions, directly from the Issuer, or upon the exercise or conversion of securities convertible into or exercisable or exchangeable for Common Stock. Each Reporting Person, upon invitation by the Issuer, may participate in any investment or strategic transaction involving the Issuer.

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Each Reporting Person also may, at any time, subject to compliance with applicable securities laws and regulatory requirements, dispose of or distribute some or all of its Common Stock or such other securities or investments it owns or may subsequently acquire such securities depending on various factors, including but not limited to, the price of shares of Common Stock, the terms and conditions of the transaction and prevailing market conditions, as well as liquidity and diversification objectives.

Based on the transactions and relationships described herein, the Reporting Persons may be deemed to constitute a “group” for purposes of Section 13(d)(3) of the Exchange Act. The filing of this Schedule 13D shall not be construed as an admission that the Reporting Persons are a group, or have agreed to act as a group, and the existence of any such group is expressly disclaimed.

Clauses (a) and (b) of Item 5 of the Schedule 13D are amended and restated in their entirety as follows:

(a) and (b)

(i) Investor beneficially owns 19,331,771 shares of Common Stock, which represents 25.4% of the outstanding Common Stock (calculated based on (i) 56,923,821 shares of Common Stock outstanding as of March 31, 2012 (as disclosed in the Form 10-Q filed by the Issuer on April 30, 2012) plus (ii) the 17,831,771 shares of Common Stock issuable upon conversion of the of the Series B Preferred Stock issued to Investor at the First Closing on February 1, 2011 and at the Second Closing on May 9, 2011, assuming a conversion price of $20.30, and (iii) after taking into account 1,500,000 shares of Common Stock purchased by Investor on May 8, 2012 pursuant to the Share Transfer (the “Calculation Method”)).

(ii) Apax Europe VII-A, L.P. may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 4,594,873 shares of Common Stock, which represents 6.0% of the outstanding Common Stock (calculated based on the Calculation Method);

(iii) Apax Europe VII-B, L.P. may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 8,430,692 shares of Common Stock, which represents 11.1% of the outstanding Common Stock (calculated based on the Calculation Method);

(iv) Apax Europe VII-1, L.P. may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 215,681 shares of Common Stock, which represents 0.3% of the outstanding Common Stock (calculated based on the Calculation Method);

(v) Apax Europe VII GP L.P. Inc. is the general partner of the Apax Europe VII Funds and, as a result, may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 13,241,246 shares of Common Stock, which represents 17.4% of the outstanding Common Stock (calculated based on the Calculation Method);

(vi) Apax Europe VII GP Co. Limited is the general partner of Apax Europe VII GP L.P. Inc., and as a result, may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 13,241,246 shares of Common Stock, which represents 17.4% of the outstanding Common Stock (calculated based on the Calculation Method);

(vii) Apax Europe VI-A, L.P. may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 5,087,726 shares of Common Stock, which represents 6.7% of the outstanding Common Stock (calculated based on the Calculation Method);

(viii) Apax Europe VI-1, L.P. may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 6,145 shares of Common Stock, which represents 0.0% of the outstanding Common Stock (calculated based on the Calculation Method);

(ix) Apax Europe VI GP L.P. Inc. is the general partner of the Apax Europe VI Funds and, as a result, may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 5,093,871 shares of Common Stock, which represents 6.7% of the outstanding Common Stock (calculated based on the Calculation Method);

(x) Apax Europe VI GP Co. Limited is the general partner of Apax Europe VI GP L.P. Inc., and as a result, may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 5,093,871 shares of Common Stock, which represents 6.7% of the outstanding Common Stock (calculated based on the Calculation Method);

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(xi) Apax Partners Europe Managers Ltd has been appointed by Apax Europe VI GP L.P. Inc. and Apax Europe VII GP L.P. Inc. as discretionary investment manager of the investments of the Apax Europe VI Funds and the Apax Europe VII Funds, respectively, and as a result, may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 18,335,117 shares of Common Stock, which represents 24.1% of the outstanding Common Stock (calculated based on the Calculation Method);

(xii) Apax Guernsey (Holdco) PCC Limited is the sole equity holder of each of Apax Europe VI GP Co. Limited and Apax Europe VII GP Co. Limited, and as a result, may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 18,335,117 shares of Common Stock, which represents 24.1% of the outstanding Common Stock (calculated based on the Calculation Method);

(xiii) Apax US Fund may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 996,654 shares of Common Stock, which represents 1.3% of the outstanding Common Stock (calculated based on the Calculation Method);

(xiv) Apax US VII GP, L.P. is the general partner of the Apax US Fund and, as a result, may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 996,654 shares of Common Stock, which represents 1.3% of the outstanding Common Stock (calculated based on the Calculation Method);

(xv) Apax US VII GP, Ltd. is the general partner of Apax US VII GP, L.P., and as a result, may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 996,654 shares of Common Stock, which represents 1.3% of the outstanding Common Stock (calculated based on the Calculation Method); and

(xvi) John F. Megrue is the sole equity holder of Apax US VII GP. Ltd., and as a result, may be deemed to beneficially own, and have shared voting and dispositive power with respect to, 996,654 shares of Common Stock, which represents 1.3% of the outstanding Common Stock (calculated based on the Calculation Method).

Prior to the vote of the shareholders of the Issuer with respect to the NASDAQ Shareholder Approval (as defined below), the Series B Preferred Stock may not be converted and the holders thereof may not vote on an as-converted basis with the holders of Common Stock. Further, prior to the receipt of the approval of the holders of Common Stock required for the removal of the Conversion Cap (as defined below) in compliance with NASDAQ Market Place Rule 5635(a), (b), (c) and (d) and NASDAQ Market Place Rule 5640, as applicable, or any similar shareholder approval rule (the “NASDAQ Shareholder Approval”), the shares of Series B Preferred Stock described herein shall not be convertible into, and the holders thereof shall not be entitled to exercise voting power with respect to, more than 19.99% of the number of shares of Common Stock outstanding immediately prior to January 10, 2011 (such limitation, the “Conversion Cap”). Dividends on each share of Series B Preferred Stock compound quarterly on each of March 15, June 15, September 15 and December 15 of each year and are added to the accrued value of such share used to calculate the number of shares of Common Stock into which such share may be converted and, therefore, subject to the prior to two sentences of this paragraph, the number of shares of Common Stock into which each share of Series B Preferred Stock may be converted is expected to increase over time.

On May 5, 2011 at the Annual Meeting of the Shareholders of the Issuer, the NASDAQ Shareholder Approval and all other necessary approvals required to remove the restrictions of the Conversion Cap were obtained. As of the date of this Amendment No. 3, the Series B Preferred Stock held by Investor is fully convertible at the Conversion Price and Investor is entitled to exercise voting power on an as-converted basis.

Neither the filing of this Schedule 13D (or any amendment or supplement thereto) nor any of its contents shall be deemed to constitute an admission by any Reporting Person, other than Investor (solely with respect to the shares of Series B Preferred Stock purchased by it pursuant to the First Closing and Second Closing of the Purchase Agreement and the Common Stock purchased on May 8, 2012), that it is the beneficial owner of any of the Series B Preferred Stock or Common Stock referred to herein for purposes of the Exchange Act, or for any other purpose, and such beneficial ownership is expressly disclaimed.

Other than Investor, the Reporting Persons are not entitled to any rights as shareholders of the Issuer.

Except as set forth in this Item 5(a), none of the Reporting Persons and, to the knowledge of the Reporting Persons, no person named in Schedule A hereto beneficially owns any Series B Preferred Stock or any Common Stock.

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Item 6 of the Schedule 13D is supplemented as follows:

On May 1, 2012, the Sellers entered into an agreement with Jefferies & Company, Inc., (“Jefferies”) providing for the sale by Jefferies of certain additional shares of Common Stock owned by the Sellers through an underwritten public offering (the “Offering”). In connection with the Offering at the request of the Sellers and the Issuer, Investor entered into a Lock-up Agreement (the “Lock-up Agreement”) with Jefferies, pursuant to which, subject to certain exceptions, Investor has agreed not to, directly or indirectly, sell, offer, contract or grant any option to sell (including without limitation any short sale), pledge, transfer, establish an open “put equivalent position” or otherwise dispose of any shares of Common Stock, options or warrants to acquire shares of Common Stock, or securities exchangeable or exercisable for or convertible into shares of Common Stock owned either of record or beneficially by Investor, or publicly announce an intention to do any of the foregoing, until the close of trading on June 29, 2012.

On May 14, 2012, Investor and the Issuer entered into a Letter Agreement (“Letter Agreement”) pursuant to which the shares of Common Stock purchased by Investor in connection with the Share Transfer shall be treated as Registrable Securities (as defined in the Investor Rights Agreement) under the Investor Rights Agreement (previously disclosed in the Original 13D). Further, under the Letter Agreement, the Issuer has agreed to, subject to certain limitations, (i) either prepare and file with the SEC one or more registration statements or amend any existing registration statement previously filed with the SEC, in each case, providing for the resale of the shares of Common Stock purchased by Investor pursuant to the Share Transfer and (ii) use its reasonable best efforts to effect the registration of such shares of Common Stock.

The foregoing summary description of the Lock-up Agreement and the Letter Agreement and the transactions contemplated thereby does not purport to be complete and is subject to and qualified in its entirety by reference to the Lock-up Agreement and the Letter Agreement, the terms of which are set forth in Exhibit 11 and Exhibit 12 hereto, respectively, and the terms of which are incorporated herein by reference.

Except for the arrangements described in the Schedule 13D, to the knowledge of the Reporting Persons, there are no contracts, arrangements, understandings or relationships (legal or otherwise) among the Reporting Persons or any other person or entity referred to in Item 2 (including those listed on Schedule A), or between such persons and any other person, with respect to any securities of the Issuer, including, but not limited to, transfer or voting of any of he securities, finder’s fees, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, division of profits or loss, or the giving or withholding of proxies.

Item 7 of the Schedule 13D is amended and restated in its entirety as follows:

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SIGNATURES

After reasonable inquiry and to the best of each of the undersigned’s knowledge and belief, each of the undersigned certify that the information set forth in this Statement is true, complete and correct.

Date: May 14, 2012

SIGNATURE PAGE TO FORM 13D FILING

SIGNATURE PAGE TO FORM 13D FILING

SIGNATURE PAGE TO FORM 13D FILING

SCHEDULE A

Set forth below is the name, citizenship, business address and the present principal occupation or employment (and the name and, to the extent not provided in the Schedule 13D to which this Schedule A is attached, the principal business and address of any organization in which such employment is conducted) of each director and executive officer of the Reporting Persons who are corporations.

EXHIBIT 4

AMENDMENT NO. 3 TO SCHEDULE 13D JOINT FILING UNDERTAKING

In accordance with the requirements of Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, and subject to the limitations set forth therein, the parties set forth below agree to jointly file the Amendment No. 3 to Schedule 13D to which this joint filing undertaking is attached, and any amendments thereto, and have duly executed this joint filing agreement as of the date set forth below.

The execution and filing of this joint filing undertaking shall not be construed as an admission that the below-named parties are a group, or have agreed to act as a group.

Dated: May 14, 2012

SIGNATURE PAGE TO JOINT FILING UNDERTAKING

SIGNATURE PAGE TO JOINT FILING UNDERTAKING

SIGNATURE PAGE TO JOINT FILING UNDERTAKING

SIGNATURE PAGE TO JOINT FILING UNDERTAKING

EXHIBIT 10

Execution Copy

COMMON STOCK PURCHASE AGREEMENT

THIS AGREEMENT is made and entered into on May 1, 2012, between Viscaria Limited, a Cyprus company (“Buyer”) and the persons and entities listed on Schedule I hereto (collectively, “Sellers”).

Sellers own shares of Common Stock, par value $0.01 per share (the “Common Stock”), of iGATE Corporation, a Pennsylvania corporation (the “Company”), and Sellers desire to sell in the aggregate 1,500,000 shares of Common Stock to Buyer, and Buyer desires to purchase such shares from Sellers pursuant to the terms and conditions of this Agreement.

NOW, THEREFORE, in consideration of the mutual covenants contained herein and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

Section 1. Purchase and Sale of Stock. At the Closing and upon the terms and conditions set forth in this Agreement, each Seller shall sell, transfer and assign to Buyer, and Buyer shall purchase from each Seller, all of such Seller’s right, title and interest in and to the number of shares of Common Stock set forth opposite such Seller’s name on Schedule I hereto (the “Shares”). The purchase price for each Share shall be $18.10.

Section 2. Closing. Subject to the terms and conditions contained in this Agreement, the purchase and sale of the Shares hereunder shall take place at the offices of Kirkland & Ellis LLP at 10:00 a.m. on May 7, 2012 (or as soon as practicable thereafter to give effect to the transfer mechanics set forth in the immediately following sentence), or at such other place or on such other date as is mutually agreeable to Buyer and Sellers (the “Closing”). At the Closing, each Seller shall deliver to Buyer documentation sufficient to credit the account of Buyer with the Shares to be sold by such Seller (or deliver to Buyer such Shares in certificated form if so requested by Buyer), and Buyer shall deliver the aggregate purchase price for the Shares purchased from each Seller by cashiers or certified check or by wire transfer of immediately available funds to a bank account designated in writing by such Seller.

Section 3. Closing Conditions.

(a) The obligation of each Seller to sell, transfer and assign the Shares to be sold to Buyer hereunder is subject to the satisfaction of the following conditions as of the Closing:

(i) the representations and warranties contained in Section 5 shall be true and correct at and as of the Closing as though then made, except to the extent of changes caused by the transactions expressly contemplated herein;

(b) The obligation of Buyer to purchase the Shares from each Seller is subject to the satisfaction of the following conditions as of the Closing:

(i) the representations and warranties contained in Section 4 shall be true and correct at and as of the Closing as though then made, except to the extent of changes caused by the transactions expressly contemplated herein;

(ii) each Seller shall have sold such Seller’s portion of the Shares simultaneously at the Closing; and

(iii) each Seller shall provided such information reasonably requested by Buyer for compliance with applicable anti-money laundering rules and policies.

Section 4. Representations and Warranties of Each Seller. Each Seller hereby represents and warrants to Buyer as follows:

(a) Ownership. All of the Shares set forth opposite such Seller’s name on Schedule I hereto are owned of record and beneficially by such Seller. At the Closing, such Seller shall transfer to Buyer good and marketable title to such Shares, free and clear of all encumbrances.

(b) Authorization. The execution and performance of this Agreement have been duly authorized by all necessary partnership action on behalf of such Seller, each Seller has full legal capacity to enter into and perform this Agreement and this Agreement has been duly authorized, executed and delivered by such Seller and constitutes a valid and legally binding obligation of such Seller, enforceable in accordance with its terms.

Section 5. Representations and Warranties of Buyer. Buyer represents and warrants to each Seller as follows:

(a) Authorization. The execution and performance of this Agreement have been duly authorized by all necessary action on the part of Buyer, and this Agreement when executed and delivered shall constitute a valid and legally binding obligation of Buyer, enforceable in accordance with its terms.

Section 6. Survival of Representations and Warranties. All representations and warranties contained herein or made in writing by any party in connection herewith shall survive the execution and delivery of this Agreement and the Closing hereunder.

Section 7. General Provisions.

(a) Complete Agreement. This Agreement constitutes the entire agreement between the parties hereto regarding the subject matter of this Agreement and supersedes and preempts any prior understandings, agreements or representations, written or oral, which may have related to the subject matter hereof.

(b) Amendment. Any provision of this Agreement may be amended or waived only with the prior written consent of Buyer and Sellers.

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(c) Counterparts. This Agreement may be executed in two or more counterparts (including by facsimile or electronic copy), each of which shall be deemed to be an original, but all of which taken together shall constitute one and the same agreement.

(d) Further Assurances. After the Closing, as and when requested by Buyer, Sellers shall, without further consideration, execute and deliver all such instruments of conveyance and transfer and shall take such further actions as Buyer may deem necessary or desirable in order to transfer the Shares to Buyer and to carry out fully the provisions and purposes of this Agreement.

(e) Successors and Assigns. This Agreement is intended to bind and inure to the benefit of and be enforceable by Buyer and Sellers and their respective successors and assigns.

(f) Choice of Law. The construction, validity, interpretation and enforcement of this Agreement shall be governed by the internal law, and not the law of conflicts, of the State of New York.

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IN WITNESS WHEREOF, the parties have executed this Common Stock Purchase Agreement on the day and year first above written.

[SIGNATURE PAGE TO COMMON STOCK PURCHASE AGREEMENT]

[SIGNATURE PAGE TO COMMON STOCK PURCHASE AGREEMENT]

SCHEDULE I

EXHIBIT 11

LOCK-UP AGREEMENT

April 30, 2012

Jefferies & Company, Inc.

520 Madison Avenue

New York, New York 10022

RE: iGATE Corporation (the “Company”)

Ladies & Gentlemen:

The undersigned is an owner of record or beneficially of certain shares of common stock, par value $0.01 per share, of the Company (“Shares”) or securities convertible into or exchangeable or exercisable for Shares. The Company and certain selling shareholders propose to enter into an underwriting agreement with Jefferies & Company, Inc. for the public offering of Shares by certain selling stockholders (the “Offering”). The undersigned recognizes that the Offering will be of benefit to the undersigned and will benefit the Company by, among other things, creating additional public float. The undersigned acknowledges that you are relying on the representations and agreements of the undersigned contained in this letter agreement in carrying out the Offering and in entering into underwriting arrangements with the Company with respect to the Offering.

In consideration of the foregoing, the undersigned hereby agrees that the undersigned will not, and will cause any spouse or immediate family member of the spouse or the undersigned living in the undersigned’s household not to, without the prior written consent of Jefferies & Company, Inc., directly or indirectly, sell, offer, contract or grant any option to sell (including without limitation any short sale), pledge, transfer, establish an open “put equivalent position” within the meaning of Rule 16a-1(h) under the Securities Exchange Act of 1934, as amended, or otherwise dispose of any Shares, options or warrants to acquire Shares, or securities exchangeable or exercisable for or convertible into Shares currently or hereafter owned either of record or beneficially (as defined in Rule 13d-3 under the Securities Exchange Act of 1934, as amended) by the undersigned (or such spouse or family member), or publicly announce an intention to do any of the foregoing, for a period commencing on the date hereof and continuing through the close of trading on the date 60 days after the date of the underwriting agreement relating to the Offering to which the Company is a party (the “Lock-up Period”); provided, that if (i) during the last 17 days of the Lock-up Period, the Company issues an earnings release or material news or a material event relating to the Company occurs or (ii) prior to the expiration of the Lock-up Period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the Lock-up Period, then, in each such case, the Lock-up Period will be extended until the expiration of the 18-day period beginning on the date of the issuance of the earnings release or the occurrence of the material news or material event, as applicable, unless Jefferies & Company, Inc. waives, in writing, such extension, except that such extension will not apply if, within three business days prior to the 15th calendar day before the last day of the Lock-up Period, the Company delivers a certificate, signed by the Chief Financial Officer or Chief Executive Officer of the Company, certifying on behalf of the Company that (a) the Shares are “actively traded securities” (as defined in Regulation M), (b) the Company meets

the applicable requirements of paragraph (a)(1) of Rule 139 under the Securities Act in the manner contemplated by FINRA Conduct Rule 2711(f)(4) and (c) the provisions of FINRA Conduct Rule 2711(f)(4) are not applicable to any research reports relating to the Company published or distributed by you during the 15 days before or after the last day of the Lock-up Period (before giving effect to such extension); provided, further, that the foregoing restrictions shall not apply to: (1) Shares acquired in open market transactions by the undersigned after the completion of the Offering, (2) the exercise of stock options on a “cashless” or “net exercise” basis in accordance with the terms thereof provided that the Shares acquired upon such exercise shall be subject to the restrictions on transfer herein, and the withholding of Shares or delivery of Shares to the Company to satisfy the tax withholding obligations related to such exercise, (3) the withholding of Shares or delivery of previously owned Shares to the Company to satisfy the tax withholding obligations arising from the vesting of restricted shares, (4) the transfer of any or all of the Shares owned by the undersigned, either during his lifetime or on death, by gift, will or intestate succession to the immediate family of the undersigned or to a trust the beneficiaries of which are exclusively the undersigned and/or a member or members of his immediate family, (5) any or all of the Shares or other Company securities if the transfer is by distribution to partners, members or shareholders of the undersigned, (6) any transfer to an affiliate of the undersigned or (7) pledges by the undersigned of Shares in favor of a lending or other similar financing source; provided, however, that, in the case of a transfer pursuant to clauses (4), (5), (6) and (7) above, it shall be a condition to such transfer that the transferee executes and delivers to Jefferies & Company, Inc. an agreement stating that the transferee is receiving and holding the Shares subject to the provisions of this letter agreement, and there shall be no further transfer of such Shares, except in accordance with this letter agreement. The undersigned hereby acknowledges and agrees that written notice of any extension of the Lock-up Period pursuant to the preceding sentence will be delivered by Jefferies & Company, Inc. to the Company and that any such notice properly delivered will be deemed to have been given to, and received by, the undersigned.

The undersigned also agrees and consents to the entry of stop transfer instructions with the Company’s transfer agent and registrar against the transfer of Shares or securities convertible into or exchangeable or exercisable for Shares held by the undersigned except in compliance with the foregoing restrictions.

With respect to the Offering only, the undersigned waives any registration rights relating to registration under the Securities Act of any Shares owned either of record or beneficially by the undersigned, including any rights to receive notice of the Offering.

This agreement is irrevocable and will be binding on the undersigned and the respective successors, heirs, personal representatives, and assigns of the undersigned.

[Signature page follows.]

EXHIBIT 12

VISCARIA LIMITED

c/o Aspen Secretarial Services

Lemesou, 77

Elia House

P.C. 2121, Nicosia, Cyprus

Attention: Devora Har-Tuv

Facsimile: +357 2241 8801

May 14, 2012

iGATE Corporation

6528 Kaiser Drive

Fremont, CA 94555

Attention: Phaneesh Murthy

Facsimile: (510)-896-2010

Ladies and Gentlemen:

Reference is made to that certain Investor Rights Agreement, dated as of February 1, 2011, by and between iGATE Corporation (“iGATE”) and Viscaria Limited (in its capacity as the Majority Sponsor Investors and holder of a majority of the outstanding Preferred Stock, “Viscaria”), as amended, restated or otherwise modified from time to time in accordance with its terms (the “Agreement”). Capitalized terms used but not defined herein shall have the respective meanings set forth in the Agreement.

On or about May 8, 2012, Viscaria acquired 1,500,000 shares of common stock of iGATE (the “Acquired Securities”). Subject to the immediately following sentence, this letter confirms that the Acquired Securities shall be treated as Registrable Securities under the Agreement. Promptly after the expiry of any contractual limitations on iGATE existing as of the date hereof that would prohibit iGATE from registering the Acquired Securities for resale by Viscaria under the Securities Act, and in any event within ninety (90) days of the date of such expiration, iGate shall (i) either prepare and file with the SEC one or more registration statements under the Securities Act on form S-3 (or, if Form S-3 is not then available to the Company, on such form of registration statement as is then available to effect a registration for resale of the Acquired Securities) or amend any existing Registration Statement previously filed with the SEC (including, without limitation, the Shelf Registration Statement), in each case, providing for the resale of the Acquired Securities by Viscaria and (ii) shall use its reasonable best efforts to effect the registration of the Acquired Securities in accordance with the terms of the Agreement.

This letter agreement and/or the interpretation and enforcement of the rights and duties of the parties hereunder or related in any way hereto shall be governed by and construed in accordance with the internal, substantive laws of the State of New York applicable to agreements entered into and

to be performed solely within such state without giving effect to the principles of conflict of laws thereof. This letter agreement may be executed by the parties hereto on any number of separate counterparts and all of said counterparts taken together shall be deemed to constitute one and the same instrument.

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Please confirm that the foregoing is in accordance with your understanding by signing in the space provided below and returning to us a duplicate of this letter agreement.

Acknowledged, agreed to and accepted as of the date set forth above by:

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