Common use of Amendment of Terms of Rights Clause in Contracts

Amendment of Terms of Rights. The terms of the Rights and the Rights Agreement may be amended in any respect without the consent of the Rights holders prior to the Distribution Date. From and after the Distribution Date, the terms of the Rights and the Rights Agreement may be amended without the consent of the Rights holders in order to cure any ambiguities or to make changes which do not adversely affect the interests of Rights holders (other than the Acquiring Person). VOTING RIGHTS: Rights will not have any voting rights. ANTI-DILUTION PROVISIONS: Rights will have the benefit of certain customary anti-dilution provisions. TAXES: The Rights distribution should not be taxable for federal income tax purposes. However, following an event which renders the Rights exercisable or upon redemption of the Rights, stockholders may recognize taxable income. The foregoing is a summary of certain principal terms of the Rights Plan only and is qualified in its entirety by reference to the Preferred Stock Rights Agreement dated as of December 31, 2007 between the Company and National City Bank, as Rights Agent as Rights Agent (the “Rights Agreement”). The Rights Agreement may be amended from time to time. A copy of the Rights Agreement was filed with the Securities and Exchange Commission as an Exhibit to a Registration Statement on Form 8-A/A. A copy of the Rights Agreement is available free of charge from the Company. The Rights represented hereby may become null and void in the circumstances specified in Section 7(e) of the Rights Agreement.

Amendment of Terms of Rights. The terms of the Rights and the Rights Agreement may be amended in any respect without the consent of the Rights holders on or prior to the Distribution Date. From and after the Distribution Date; thereafter, the terms of the Rights and the Rights Agreement may be amended without the consent of the Rights holders in order to cure any ambiguities or to make changes which do not adversely affect the interests of Rights holders (other than the Acquiring Person). VOTING RIGHTSVoting Rights: Rights will not have any voting rights. ANTIAnti-DILUTION PROVISIONSDilution Provisions: Rights will have the benefit of certain customary anti-dilution provisions. TAXESTaxes: The Rights distribution should not be taxable for federal income tax purposes. However, following an event which renders the Rights exercisable or upon redemption of the Rights, stockholders may recognize taxable income. The foregoing is a summary of certain principal terms of the Stockholder Rights Plan only and is qualified in its entirety by reference to the Preferred Stock Rights Agreement dated amended and restated as of December 31October 8, 2007 2002 between the Company and National City BankEquiServe Trust Company, as Rights Agent N.A. as Rights Agent (the “Rights Agreement”). The Rights Agreement may be amended from time to time. A copy of the Rights Agreement as amended and restated was filed with the Securities and Exchange Commission as an Exhibit to a an amended Registration Statement on Form 8-A/A. A dated October 8, 2002. A copy of the Rights Agreement is available free of charge from the Company. The Rights represented hereby may become null and void in the circumstances specified in Section 7(e) of the Rights Agreement.

Amendment of Terms of Rights. The terms of the Rights and the Rights Agreement may be amended in any respect without the consent of the Rights holders on or prior to the Distribution Date. From and after the Distribution Date; thereafter, the terms of the Rights and the Rights Agreement may be amended without the consent of the Rights holders in order to cure any ambiguities or to make changes which do not adversely affect the interests of Rights holders (other than the Acquiring Person). VOTING RIGHTS: Rights will not have any voting rights. ANTI-DILUTION PROVISIONS: Rights will have the benefit of certain customary anti-dilution provisions. TAXES: The Rights distribution should not be taxable for federal income tax purposes. However, following an event which renders the Rights exercisable or upon redemption of the Rights, stockholders may recognize taxable income. The foregoing is a summary of certain principal terms of the Rights Plan Agreement only and is qualified in its entirety by reference to the Preferred Stock Rights Agreement dated as of December 31November 8, 2007 2002 between the Company and National City BankAmerican Stock Transfer & Trust Company as Rights Agent, as Rights Agent as Rights Agent amended (the “Rights Agreement”). The Rights Agreement may be amended from time to time. A copy of the Rights Agreement was filed with the Securities and Exchange Commission as an Exhibit to a Registration Statement on Form 8-A/A. A dated November 14, 2002, and amendments to the Rights Agreement were filed with the Securities and Exchange Commission as an Exhibit to a Form 8-K on each of December 11, 2008, and November 16, 2009. A copy of the Rights Agreement is available free of charge from the Company. The Rights represented hereby may become null and void in the circumstances specified in Section 7(e) of the [Annex B to Rights Agreement.]

Amendment of Terms of Rights. The terms of the Rights and the Rights Agreement may be amended in any respect without the consent of the Rights holders on or prior to the Distribution Date. From and after the Distribution Date; thereafter, the terms of the Rights and the Rights Agreement may be amended without the consent of the Rights holders in order to cure any ambiguities or to make changes which do not adversely affect the interests of Rights holders (other than the Acquiring Person). VOTING RIGHTSVoting Rights: Rights will not have any voting rights. ANTIAnti-DILUTION PROVISIONSDilution Provisions: Rights will have the benefit of certain customary anti-dilution provisions. TAXESTaxes: The Rights distribution should not be taxable for federal income tax purposes. However, following an event which renders the Rights exercisable or upon redemption of the Rights, stockholders shareholders may recognize taxable income. The foregoing is a summary of certain principal terms of the Shareholder Rights Plan only and is qualified in its entirety by reference to the Preferred Stock Rights Agreement dated as of December 31June 7, 2007 2004 between the Company and National City BankComputershare Shareowner Services LLC (f/k/a Mellon Investor Services LLC), as Rights Agent Agent, as Rights Agent amended as of April 9, 2012 (as amended, the “Rights Agreement”). The Rights Agreement may be further amended from time to time. A copy of the Rights Agreement was filed with the Securities and Exchange Commission as an Exhibit to a Registration Statement on Form 8-A dated June 8, 2004. A copy of an amendment to the Rights Agreement was filed with the Securities and Exchange Commission as an Exhibit to an amendment to a Registration Statement on Form 8-A/A. A copy dated April 9, 2012. Copies of the Rights Agreement is and such amendment are available free of charge from the Company. The Rights represented hereby may become null and void in the circumstances specified in Section 7(e) of the Rights Agreement.

Amendment of Terms of Rights. The terms of the Rights and the Rights Agreement may be amended in any respect without the consent of the Rights holders on or prior to the Distribution Date. From and after the Distribution Date; thereafter, the terms of the Rights and the Rights Agreement may be amended without the consent of the Rights holders in order to cure any ambiguities or to make changes which do not adversely affect the interests of Rights holders (other than the Acquiring Person). VOTING RIGHTSVoting Rights: Rights will not have any voting rights. ANTIAnti-DILUTION PROVISIONSDilution Provisions: Rights will have the benefit of certain customary anti-dilution provisions. TAXESTaxes: The Rights distribution should not be taxable for federal income tax purposes. However, following an event which renders the Rights exercisable or upon redemption of the Rights, stockholders may recognize taxable income. The foregoing is a summary of certain principal terms of the Amended and Restated Stockholder Rights Plan only and is qualified in its entirety by reference to the Amended and Restated Preferred Stock Rights Agreement Agreement, dated as of December 31January 29, 2007 2004, between the Company and National City BankXxxxx Fargo Bank Minnesota, as Rights Agent N.A. as Rights Agent (the “"Rights Agreement”"). The Rights Agreement may be amended from time to time. A copy of the Rights Agreement was filed with the Securities and Exchange Commission as an Exhibit to a Registration Statement on Form 8-A/A. A dated January 29, 2004. A copy of the Rights Agreement is available free of charge from the Company. The Rights represented hereby may become null and void in the circumstances specified in Section 7(e) of the Rights Agreement.QuickLinks Exhibit 4.20