(a)

Schedule 1.01 (Mandatory Cost Formulae Schedule) to the Credit Agreement is hereby deleted in its entirety;

(b)

Schedule 2.01 (Commitments and Applicable Percentages Schedule) to the Credit Agreement is hereby replaced in its entirety by Schedule 2.01 attached hereto;

(c)

Schedule 2.07(a) (Term Loan Repayment Schedule) to the Credit Agreement is hereby replaced in its entirety by Schedule 2.07(a) attached hereto;

(d)

Schedule 10.02 (Administrative Agent's Office; Certain Addresses for Notice Schedule) to the Credit Agreement is hereby replaced in its entirety by Schedule 10.02 attached hereto;

(e)

Exhibit D (Form of Compliance Certificate) to the Credit Agreement is hereby replaced in its entirety by Exhibit D attached hereto;

(f)

Exhibit F (Form of Guaranty) to the Credit Agreement is hereby replaced in its entirety by Exhibit F attached hereto;

(g)

Exhibit G (Form of Pledge Agreement) to the Credit Agreement is hereby replaced in its entirety by Exhibit G attached hereto; and

(h)

Exhibit H (Form of Security Agreement) to the Credit Agreement is hereby replaced in its entirety by Exhibit H attached hereto.

(a)

the Guaranty shall be amended so that it reads as set forth in Exhibit F hereto;

(b)

the Pledge Agreement shall be amended so that it reads as set forth in Exhibit G hereto; and

(c)

the Security Agreement shall be amended so that it reads as set forth in Exhibit H hereto.

(a)

The Administrative Agent shall have received counterparts of this First Amendment, duly executed by the Borrower, each Guarantor, the Administrative Agent and each of the Lenders, which counterparts may be delivered by telefacsimile or other electronic means (including .pdf), but such delivery will be promptly followed by the delivery of four (4) original signature pages by each Person party hereto unless waived by the Administrative Agent;

(b)

the Administrative Agent shall have received, in form and substance reasonably acceptable to the Administrative Agent, such certificates of resolutions or other action, incumbency certificates and/or other certificates of Responsible Officers of each Loan Party as the Administrative Agent may reasonably require evidencing the identity, authority and capacity of each Responsible Officer thereof authorized to act as a Responsible Officer, in connection with this Agreement and the other Loan Documents to which such Loan Party is a party (it being understood that such certificates, resolutions and other actions shall be reasonably acceptable if substantially similar in form and substance (with such adjustments as are customary in connection with an amendment of the type described herein) to those delivered in connection with the original closing of the Credit Agreement);

(c)

the Administrative Agent shall have received such customary documents and certifications to evidence that each Loan Party is duly organized or formed, and that each Loan Party is validly existing and in good standing in its jurisdiction of organization;

(d)

each requesting Term Loan Lender (including any Additional Term Loan Lender, if any) shall have received a Term Loan Note executed by the Borrower in favor of such Term Loan Lender;

(e)

the Administrative Agent shall have received favorable opinions of Wachtell, Lipton, Rosen & Katz, as New York counsel to the Loan Parties, Potter Anderson Corroon LLP, as Delaware counsel to the Loan Parties, and H. Carol Bernstein, General Counsel to the Borrower, as to this First Amendment and in form and substance reasonably satisfactory to the Administrative Agent;

(f)

the Administrative Agent shall have received a solvency certificate signed by a Responsible Officer of the Borrower as to the Solvency of the Borrower and its Subsidiaries as of the Closing Date;

(g)

the Administrative Agent shall have received a certificate signed by a Responsible Officer of the Borrower certifying that there has been no event or circumstance since December 31, 2013 that has had or could be reasonably expected to have, either individually or in the aggregate, a Material Adverse Effect; and

(h)

 (i) the Borrower shall have paid to the Administrative Agent, for the account of each Lender executing this First Amendment by 5:00 p.m. New York Time on [June 26], 2014, an upfront fee, equal to ten basis points (10 "bps") multiplied by (A) in the case of the Revolving Credit Lenders (including any such Person that becomes a Lender to the Credit Agreement pursuant to an assignment in connection herewith), each such Revolving Credit Lender's Revolving Credit Commitment immediately after giving effect to this First Amendment and (B) in the case of the Term Loan Lenders (including any such Person that becomes a Lender to the Credit Agreement pursuant to an assignment in connection herewith), each such Term Lender's Outstanding Amount of Term Loans immediately after giving effect to this First Amendment; and (ii) the Borrower shall have paid any fees required to be paid on the First Amendment Effective Date pursuant to that certain Engagement Letter dated as of May 1, 2014 by and among the Borrower, the Administrative Agent and MLPFS shall have been paid.

(a)

The representations and warranties made by each of the Borrower and each other Loan Party in Article V of the Credit Agreement and in each of the other Loan Documents to which they are a party are true and correct in all material respects on and as of the date hereof, except to the extent that such representations and warranties expressly relate to an earlier date, in which case they shall be true and correct in all material respects as of such earlier date;

(b)

This First Amendment has been duly authorized, executed and delivered by each of the Loan Parties and constitutes a legal, valid and binding obligation of such parties, subject to applicable bankruptcy, insolvency, reorganization, moratorium or other Laws affecting creditors' rights generally and subject to general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law);

(c)

The Persons appearing as Guarantors on the signature pages to this First Amendment constitute all Persons who are required to be Guarantors pursuant to the terms of the Credit Agreement and the other Loan Documents (in each case as amended hereby and after giving effect to Section 6 hereof), including without limitation all Persons who became Domestic Subsidiaries and were required to become Guarantors after the Closing Date, and each of such Persons has become and remains a party to a Guaranty as a Guarantor to the extent required by the terms of the Credit Agreement (as amended hereby); and

(d)

As of the First Amendment Effective Date, no Default or Event of Default has occurred and is continuing.

(a)

As a result of Cabot Microelectronics Global Corporation ("CMGC") ceasing to be a Domestic Subsidiary after giving effect to the amendments contemplated hereby, immediately after the effectiveness hereof, (i) CMGC shall automatically be released as a Guarantor under the Guaranty and as a Pledgor under and as defined in each of the Security Agreement, the Pledge Agreement and the IP Security Agreement, (ii) all of CMGC's Obligations shall automatically be terminated, (iii) all of the Liens and other charges of whatever nature granted in respect of CMGC's assets will be automatically released and of no further force and effect, and (iv) the pledge by the Borrower of the 35% of the Voting Equity Interests (as defined in the Pledge Agreement) of CMGC shall automatically be released and of no further force and effect such that the total amount of the Voting Equity Interests (as defined in the Pledge Agreement) of CMGC that is pledged as collateral security for the payment, performance and satisfaction of the Secured Obligations to the Administrative Agent for the benefit of the Secured Parties immediately after giving effect to this Section 6 shall be limited to 65% of the Voting Equity Interests of CMGC.

(b)

In furtherance of the foregoing, at the expense of the Borrower, the Administrative Agent will (and each of the parties hereto authorizes the Administrative Agent to) promptly following effectiveness hereof (and from time to time as reasonably requested by the Borrower or CMGC thereafter), (i) execute and deliver to the Loan Parties (or any designee of the Loan Parties, including their counsel) any such lien releases, discharges of security interests, pledges or guarantees and other similar discharge or release documents, as are reasonably requested to release, as of record, the liens and security interests described in the foregoing paragraph granted by (or related to) CMGC under the Loan Documents and (ii) deliver to the Borrower (or any designee of the Borrower) all instruments evidencing pledged debt and all pledged equity certificates and any other similar collateral related to CMGC (together with related transfer powers, if any) previously delivered in physical form by the Loan Parties to the Administrative Agent to the extent that such instruments, certificates or similar collateral constitute collateral of the type described in the foregoing paragraph.

(a)

Each Guarantor hereby consents, acknowledges and agrees to the First Amendment and hereby reaffirms in all respects the Guaranty (including without limitation the continuation of such Guarantor's payment and performance obligations thereunder upon and after the First Amendment Effective Date) and the enforceability of the Guaranty against such Guarantor in accordance with its terms, subject to applicable bankruptcy, insolvency, reorganization, moratorium or other Laws affecting creditors' rights generally and subject to general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law).

(b)

Each of the Borrower and each Guarantor that is a party to the Security Agreement hereby reaffirms its grant pursuant to the Security Agreement, as collateral security for the payment, performance and satisfaction of its Secured Obligations (for purposes hereof, as such term is defined in the Credit Agreement after giving effect hereto), to the Administrative Agent for the benefit of the Secured Parties a continuing first priority security interest in and to the Collateral (as defined in the Security Agreement).

(c)

Each of the Borrower and each Guarantor that is a party to the Pledge Agreement hereby reaffirms its grant pursuant to the Pledge Agreement, as collateral security for the payment, performance and satisfaction of its Secured Obligations, to the Administrative Agent for the benefit of the Secured Parties a continuing security interest in and to the Collateral (as defined in the Pledge Agreement).

(d)

Each of the Borrower and each Guarantor that is a party to the IP Security Agreement hereby reaffirms its grant pursuant to the IP Security Agreement, as collateral security for the payment, performance and satisfaction of its Secured Obligations, to the Administrative Agent for the benefit of the Secured Parties a continuing security interest in and to the Collateral (as defined in the IP Security Agreement).

(e)

Each of the Borrower and each Guarantor agrees that (except as described in Section 6 hereof) nothing contained herein will operate to impair or adversely affect the priority of the Liens and security interests granted by the Loan Parties as security for the Secured Obligations.