Common use of FORM OF U.S. TAX COMPLIANCE CERTIFICATE Clause in Contracts

FORM OF U.S. TAX COMPLIANCE CERTIFICATE. (For Foreign Participants That Are Not Partnerships For U.S. Federal Income Tax Purposes) Reference is hereby made to the Third Amended and Restated Credit Agreement, dated as of April 14, 2020 (as amended, supplemented or otherwise modified from time to time, the “Credit Agreement”), among IDEXX Laboratories, Inc., a Delaware corporation (the “Administrative Borrower”), IDEXX Distribution, Inc., a Massachusetts corporation, IDEXX Operations, Inc., a Delaware corporation, OPTI Medical Systems, Inc., a Delaware corporation, IDEXX Laboratories Canada Corporation, a company formed under the laws of Canada, IDEXX Europe B.V., a private limited liability company formed under the laws of the Netherlands, and IDEXX Holding B.V., a private limited liability company formed under the laws of the Netherlands (collectively with the Administrative Borrower and all other Persons who heretofore have been or hereafter may be designated as a Borrower pursuant to Section 2.21 thereof, the “Borrowers”), the Lenders party thereto, JPMorgan Chase Bank, N.A., as Administrative Agent, and JPMorgan Chase Bank, N.A., Toronto Branch, as Toronto Agent. Pursuant to the provisions of Section 2.16 of the Credit Agreement, the undersigned hereby certifies that (i) it is the sole record and beneficial owner of the participation in respect of which it is providing this certificate, (ii) it is not a “bank” within the meaning of Section 881(c)(3)(A) of the Code, (iii) it is not a “10 percent shareholder” (within the meaning of Section 881(c)(3)(B) of the Code) of any Borrower that is a US Person, and (iv) it is not a “controlled foreign corporation” (as described in Section 881(c)(3)(C) of the Code) related to any Borrower that is a US Person. The undersigned has furnished its participating Lender with a certificate of its non-US Person status on IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable. By executing this certificate, the undersigned agrees that (1) if the information provided on this certificate changes, the undersigned shall promptly so inform such Lender in writing and (2) the undersigned shall have at all times furnished such Lender with a properly completed and currently effective certificate in either the calendar year in which each payment is to be made to the undersigned, or in either of the two calendar years preceding such payments. Unless otherwise defined herein, terms defined in the Credit Agreement and used herein shall have the meanings given to them in the Credit Agreement. [NAME OF PARTICIPANT] By: Name: Title: Date: EXHIBIT H-4

FORM OF U.S. TAX COMPLIANCE CERTIFICATE. (For Foreign Participants Lenders That Are Not Partnerships For U.S. Federal Income Tax Purposes) Reference is hereby made to the Third Amended and Restated Credit Agreement, dated as of April 14, 2020 (as amended, supplemented or otherwise modified from time to time, the “Credit Agreement”), among IDEXX Laboratories, Inc., a Delaware corporation (the “Administrative Borrower”), IDEXX Distribution, Inc., a Massachusetts corporation, IDEXX Operations, Inc., a Delaware corporation, OPTI Medical Systems, Inc., a Delaware corporation, IDEXX Laboratories Canada Corporation, a company formed under the laws of Canada, IDEXX Europe B.V., a private limited liability company formed under the laws of the Netherlands, and IDEXX Holding B.V., a private limited liability company formed under the laws of the Netherlands (collectively with the Administrative Borrower and all other Persons who heretofore have been or hereafter may be designated as a Borrower pursuant to Section 2.21 thereof, the “Borrowers”), the Lenders party thereto, JPMorgan Chase Bank, N.A., as Administrative Agent, and JPMorgan Chase Bank, N.A., Toronto Branch, as Toronto Agent. Pursuant to the provisions of Section 2.16 of the Credit Agreement, the undersigned hereby certifies that (i) it is the sole record and beneficial owner of the participation Loan(s) (as well as any promissory note(s) evidencing such Loan(s)) in respect of which it is providing this certificate, (ii) it is not a “bank” within the meaning of Section 881(c)(3)(A) of the Code, (iii) it is not a “10 percent shareholder” (within the meaning of Section 881(c)(3)(B) of the Code) of any Borrower that is a US Person, and (iv) it is not a “controlled foreign corporation” (as described in Section 881(c)(3)(C) of the Code) related to any Borrower that is a US Person. The undersigned has furnished its participating Lender the Administrative Agent and the Administrative Borrower with a certificate of its non-US Person status on IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable. By executing this certificate, the undersigned agrees that (1) if the information provided on this certificate changes, the undersigned shall promptly so inform such Lender in writing the Administrative Borrower and the Administrative Agent and (2) the undersigned shall have at all times furnished such Lender the Administrative Borrower and the Administrative Agent with a properly completed and currently effective certificate in either the calendar year in which each payment is to be made to the undersigned, or in either of the two calendar years preceding such payments. Unless otherwise defined herein, terms defined in the Credit Agreement and used herein shall have the meanings given to them in the Credit Agreement. [NAME OF PARTICIPANTLENDER] By: Name: Title: Date: EXHIBIT H-4H-2

FORM OF U.S. TAX COMPLIANCE CERTIFICATE. (For Foreign Participants Lenders That Are Not Partnerships For U.S. Federal Income Tax Purposes) Reference is hereby made to the Third Amended and Restated Credit Agreement, dated as of April 14, 2020 (as amended, supplemented or otherwise modified from time to time, the “Credit Agreement”), among IDEXX Laboratories, Inc., a Delaware corporation (the “Administrative Borrower”), IDEXX Distribution, Inc., a Massachusetts corporation, IDEXX Operations, Inc., a Delaware corporation, OPTI Medical Systems, Inc., a Delaware corporation, IDEXX Laboratories Canada Corporation, a company formed under the laws of Canada, IDEXX Europe B.V., a private limited liability company formed under the laws of the Netherlands, and IDEXX Holding B.V., a private limited liability company formed under the laws of the Netherlands (collectively with the Administrative Borrower and all other Persons who heretofore have been or hereafter may be designated as a Borrower pursuant to Section 2.21 thereof, the “Borrowers”), the Lenders party thereto, JPMorgan Chase Bank, N.A., as Administrative Agent, and JPMorgan Chase Bank, N.A., Toronto Branch, as Toronto Agent. Pursuant to the provisions of Section 2.16 of the Credit Agreement, the undersigned hereby certifies that (i) it is the sole record and beneficial owner of the participation Loan(s) (as well as any promissory note(s) evidencing such Loan(s)) in respect of which it is providing this certificate, (ii) it its direct or indirect partners/members are the sole beneficial owners of such Loan(s) (as well as any promissory note(s) evidencing such Loan(s)), (iii) with respect to the extension of credit pursuant to this Credit Agreement or any other Loan Document, neither the undersigned nor any of its direct or indirect partners/members is not a “bank” bank extending credit pursuant to a loan agreement entered into in the ordinary course of its trade or business within the meaning of Section 881(c)(3)(A) of the Code, (iiiiv) it none of its direct or indirect partners/members is not a “10 percent shareholder” (within the meaning of Section 881(c)(3)(B) of the Code) of any Borrower that is a US Person, and (ivv) it none of its direct or indirect partners/members is not a “controlled foreign corporation” (as described in Section 881(c)(3)(C) of the Code) related to any Borrower that is a US Person. The undersigned has furnished its participating Lender the Administrative Agent and the Administrative Borrower with a certificate IRS Form W-8IMY accompanied by one of the following forms from each of its non-US Person status on partners/members that is claiming the portfolio interest exemption: (i) an IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, (ii) an IRS Form W-8IMY accompanied by an IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, from each of such partner’s/member’s beneficial owners that is claiming the portfolio interest exemption. By executing this certificate, the undersigned agrees that (1) if the information provided on this certificate changes, the undersigned shall promptly so inform such Lender in writing the Administrative Borrower and the Administrative Agent and (2) the undersigned shall have at all times furnished such Lender the Administrative Borrower and the Administrative Agent with a properly completed and currently effective certificate in either the calendar year in which each payment is to be made to the undersigned, or in either of the two calendar years preceding such payments. Unless otherwise defined herein, terms defined in the Credit Agreement and used herein shall have the meanings given to them in the Credit Agreement. [NAME OF PARTICIPANTLENDER] By: Name: Title: Date: EXHIBIT H-4H-3

FORM OF U.S. TAX COMPLIANCE CERTIFICATE. (For Foreign Participants That Are Not Partnerships For U.S. Federal Income Tax Purposes) Reference is hereby made to the Third Amended and Restated Credit Agreement, dated as of April 14, 2020 (as amended, supplemented or otherwise modified from time to time, the “Credit Agreement”), among IDEXX Laboratories, Inc., a Delaware corporation (the “Administrative Borrower”), IDEXX Distribution, Inc., a Massachusetts corporation, IDEXX Operations, Inc., a Delaware corporation, OPTI Medical Systems, Inc., a Delaware corporation, IDEXX Laboratories Canada Corporation, a company formed under the laws of Canada, IDEXX Europe B.V., a private limited liability company formed under the laws of the Netherlands, and IDEXX Holding B.V., a private limited liability company formed under the laws of the Netherlands (collectively with the Administrative Borrower and all other Persons who heretofore have been or hereafter may be designated as a Borrower pursuant to Section 2.21 thereof, the “Borrowers”), the Lenders party thereto, JPMorgan Chase Bank, N.A., as Administrative Agent, and JPMorgan Chase Bank, N.A., Toronto Branch, as Toronto Agent. Pursuant to the provisions of Section 2.16 of the Credit Agreement, the undersigned hereby certifies that (i) it is the sole record and beneficial owner of the participation in respect of which it is providing this certificate, (ii) it its direct or indirect partners/members are the sole beneficial owners of such participation, (iii) with respect such participation, neither the undersigned nor any of its direct or indirect partners/members is not a “bank” bank extending credit pursuant to a loan agreement entered into in the ordinary course of its trade or business within the meaning of Section 881(c)(3)(A) of the Code, (iiiiv) it none of its direct or indirect partners/members is not a “10 percent shareholder” (within the meaning of Section 881(c)(3)(B) of the Code) of any Borrower that is a US Person, and (ivv) it none of its direct or indirect partners/members is not a “controlled foreign corporation” (as described in Section 881(c)(3)(C) of the Code) related to any Borrower that is a US Person. The undersigned has furnished its participating Lender with a certificate IRS Form W-8IMY accompanied by one of the following forms from each of its non-US Person status on partners/members that is claiming the portfolio interest exemption: (i) an IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, or (ii) an IRS Form W-8IMY accompanied by an IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, from each of such partner’s/member’s beneficial owners that is claiming the portfolio interest exemption. By executing this certificate, the undersigned agrees that (1) if the information provided on this certificate changes, the undersigned shall promptly so inform such Lender in writing and (2) the undersigned shall have at all times furnished such Lender with a properly completed and currently effective certificate in either the calendar year in which each payment is to be made to the undersigned, or in either of the two calendar years preceding such payments. Unless otherwise defined herein, terms defined in the Credit Agreement and used herein shall have the meanings given to them in the Credit Agreement. [NAME OF PARTICIPANT] By: Name: Title: Date: EXHIBIT H-4: