Exhibit 4.2 INSIGHT MIDWEST, L.P. and INSIGHT CAPITAL, INC. As Issuers and THE BANK OF NEW YORK As Trustee ----------------- SECOND SUPPLEMENTAL INDENTURE Dated as of October 12, 2005 (Supplemental to Indenture Dated as of November 6, 2000) Series A and Series B 10 1/2% Senior Notes Due 2010 SECOND SUPPLEMENTAL INDENTURE, dated as of October 12, 2005 (this "Second Supplemental Indenture") among Insight Midwest, L.P., a Delaware limited partnership (the "Company"), Insight Capital, Inc., a Delaware corporation ("Insight Capital" and together with the Company, the "Issuers"), and The Bank of New York, a New York banking corporation, as Trustee (the "Trustee"). WHEREAS, the Issuers executed and delivered an Indenture dated as of November 6, 2000 (as the same has been amended or supplemented to the date hereof, the "Indenture") between the Issuers and the Trustee, as trustee, providing for the issue of the Issuers' Series A and Series B 10 1/2% Senior Notes Due 2010; and WHEREAS, Section 9.02 of the Indenture provides that compliance with Section 4.15 of the Indenture may be waived with the consent of the Record Holders of a majority in principal amount of the then outstanding Notes voting as a single class; and WHEREAS, pursuant to the Consent Solicitation Statement dated September 28, 2005, as it has been amended or supplemented to the date hereof ("Consent Solicitation Statement"), the Issuers have solicited a waiver (the "Waiver") from the Record Holders (as defined herein) with respect to any requirement under the Indenture that the Issuers or any other person may have to make a Change of Control Offer under Section 4.15 of the Indenture as a result of the execution and delivery of certain agreements and the consummation of certain transactions in connection with the Merger (as defined herein); WHEREAS, in accordance with Section 9.02 of the Indenture, the Issuers have received the written consent of the Record Holders of at least a majority in principal amount of the outstanding Notes voting as a single class to the Waiver; WHEREAS, pursuant to an Officers' Certificate, the Issuers have directed the Trustee to enter into this Second Supplemental Indenture; and WHEREAS, all conditions and requirements necessary to make this Second Supplemental Indenture a valid and binding instrument in accordance with its terms and the terms of the Indenture have been satisfied, including, without limitation, the delivery to the Trustee of an Opinion of Counsel. NOW, THEREFORE, in consideration of the premises and of the mutual covenants herein contained, the Issuers and the Trustee hereby covenant and agree as follows: SECTION 1. DEFINED TERMS. For all purposes of this Second Supplemental Indenture, the following terms shall have the following meaning: "Carlyle" means Carlyle Partners III Telecommunications, L.P., Carlyle Partners IV Telecommunications, L.P., CP III Coinvestment, L.P. and CP IV Coinvestment, L.P., individually and collectively. "Consent Date" means 5:00 p.m., New York City time, on October 12, 2005, as extended by the Issuers. "Consent Payment" means the cash payment to be made on the Consent Payment Date to the Trustee for the benefit of the Record Holders who consent to the proposed Waiver on or prior to the Consent Date and do not withdraw such consent prior to the Effective Time in the amount, and on the terms and subject to the conditions, specified in the Consent Solicitation Statement. "Consent Payment Date" means a date promptly following consummation of the Merger and designated by the Issuers. "Continuing Investors" means Sidney R. Knafel, Michael S. Willner, Andrew G. Knafel, the Knafel Children Trusts, Thomas Kempner, James Marcus and any other persons who become parties to the Exchange Agreement prior to consummation of the Merger. "Effective Time" means 5:01 P.M., New York City time, on October 12, 2005. "Exchange Agreement" means the Exchange Agreement, dated as of July 28, 2005, by and among Insight, Insight Acquisition, the Continuing Investors and Carlyle, as the same may from time to time be amended, modified, supplemented or restated. "Insight" means Insight Communications Company, Inc., a Delaware corporation. "Insight Acquisition" means Insight Acquisition Corp., a Delaware corporation. "Knafel Children Trusts" means the Trust F/B/O Andrew G. Knafel, dated September 13, 1978, the Trust F/B/O Douglas R. Knafel, dated September 13, 1978, the Trust F/B/O Andrew G. Knafel and Douglas R. Knafel, dated July 16, 1976, and the Trust F/B/O Douglas R. Knafel, dated November 6, 1983, individually and collectively. "Merger" means the proposed merger of Insight Acquisition with and into Insight as contemplated by the Merger Agreement. "Merger Agreement" means the Agreement and Plan of Merger, dated as of July 28, 2005, by and between Insight Acquisition and Insight, as the same may from time to time be amended, modified, supplemented or restated. "Principals' Agreement" means the Principals' Agreement, dated as of July 28, 2005, by and among Sidney R. Knafel, Michael S. Willner and Carlyle, in each case as the same may from time to time be amended, modified, supplemented or restated. "Record Holder" means each Holder of record as of the close of business in New York City on September 26, 2005. "Securityholders Agreement" means the Securityholders Agreement to be entered into concurrently with the consummation of the Merger by Insight, Carlyle, the Continuing Investors and each other person who becomes a party thereto as contemplated thereunder, as the same may from time to time be amended, modified, supplemented or restated. "Termination Date" means the later of (A) the February 15, 2006 termination date specified in Section 7.01(b)(i) of the Merger Agreement or (B) the date the Merger Agreement is terminated, but in no event later than the 60th day after February 15, 2006. "Transactions" means the Merger and the other transactions consummated pursuant to the Transaction Agreements in connection with the closing of the Merger. "Transaction Agreements" means the Merger Agreement, the Exchange Agreement, the Voting Agreement, the Principals' Agreement, the Securityholders Agreement and the other agreements and instruments executed and delivered in connection therewith, in each case by the parties contemplated thereunder and as the same may from time to time be amended, modified, supplemented or restated. "Voting Agreement" means the Insight Voting Agreement dated as of July 28, 2005 between Insight Acquisition, Sidney R. Knafel, Michael S. Willner, Andrew G. Knafel and the Knafel Children Trusts, in each case as the same may from time to time be amended, modified, supplemented or restated. Except as otherwise expressly provided or unless the context otherwise requires, all capitalized terms defined herein shall have the meanings assigned to them herein. All capitalized terms defined in the Indenture and not defined herein shall have the meanings assigned to them in the Indenture. SECTION 2. WAIVER OF SECTION 4.15 OF INDENTURE. Subject to payment of the Consent Payment on or before the Consent Payment Date by the Issuer to the Trustee for the benefit of the Record Holders entitled to such Consent Payment under the terms and subject to the conditions set forth in the Consent Solicitation Statement, the provisions of Section 4.15 of the Indenture are hereby waived in all respects as the same may relate to: (i) the execution and delivery of the Transaction Agreements by the parties contemplated thereunder, and (ii) the consummation of the Transactions on or prior to the Termination Date. SECTION 3. EFFECT ON ORIGINAL INDENTURE. This Second Supplemental Indenture shall be immediately effective at the Effective Time and form a part of the Indenture for all purposes relating to the Notes and every holder of the Notes heretofore or thereafter authenticated under the Indenture as supplemented hereby, shall be bound hereby, provided that, in the event the Merger is not consummated on or prior to the Termination Date and the Consent Payment is not made to the Record Holders entitled thereto, the Waiver and Section 2 of this Second Supplemental Indenture will have no further effect. The Indenture as supplemented by this Second Supplemental Indenture is hereby in all respects ratified and confirmed. SECTION 4. COUNTERPARTS. This Second Supplemental Indenture may be executed in any number of counterparts, each of which shall be an original; but such counterparts shall together constitute but one and the same instrument. SECTION 5. TRUSTEE MAKES NO REPRESENTATIONS. The Trustee makes no representations as to the validity or sufficiency of this Second Supplemental Indenture. The statements and recitals herein are deemed to be those of the Issuers and not of the Trustee. [SIGNATURE PAGE FOLLOWS] IN WITNESS WHEREOF, the parties hereto have caused this Second Supplemental Indenture to be duly executed, all as of the day and year first written above. INSIGHT MIDWEST, L.P. By its General Partner, Insight Communications Company, L.P. By its General Partner, Insight Communications Company, Inc. By: /s/ John Abbot ------------------------------------- Name: John Abbot Title: Senior Vice President & Chief Financial Officer INSIGHT CAPITAL, INC. By: /s/ John Abbot ------------------------------------- Name: John Abbot Title: Senior Vice President & Chief Financial Officer THE BANK OF NEW YORK as Trustee By: /s/ Robert A. Massimillo ------------------------------------- Name: Robert A. Massimillo Title: Vice President