Company: AILIM
Filing Date: 2025-09-16
Form Type: 424B2
Source: 0001104659-25-090464
Chunk: 59

Company: Ameren Illinois Co
Filing Date: 2025-09-16
Form: 424B2
Chunk 59
---
. and its affiliates.

The Bank of New York Mellon Trust Company, N.A. is also acting as trustee under the mortgage indenture, our senior note indenture dated as of June 1, 2006, that was originally executed by Central Illinois Light Company (“CILCO”), and our senior note indenture dated as of December 1, 1998. As trustee under the senior secured indenture, The Bank of New York Mellon Trust Company, N.A. could have a conflicting interest for purposes of the Trust Indenture Act of 1939 if an event of default were to occur under the senior secured indenture. In that case, the senior secured trustee may be required to eliminate such conflicting interest by resigning as senior secured trustee. There are other instances under the Trust Indenture Act of 1939 which would require the resignation of the senior secured trustee if a senior secured indenture event of default were to occur.

#### Governing Law
The senior secured indenture is, and the senior secured debt securities will be, governed by New York law.

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TABLE OF CONTENTS

### DESCRIPTION OF FIRST MORTGAGE BONDS AND MORTGAGE INDENTURE

#### General
The first mortgage bonds will be issued in one or more series under our General Mortgage Indenture and Deed of Trust dated as of November 1, 1992, between us (as successor to IP) and The Bank of New York Mellon Trust Company, N.A., as successor mortgage trustee, as supplemented, modified and amended by various supplemental indentures, which we collectively refer to as the “mortgage indenture.” The mortgage indenture and the form of supplemental indenture establishing the first mortgage bonds of a particular series are exhibits to, or will be subsequently incorporated by reference into, the registration statement of which this prospectus is a part. The mortgage indenture has been qualified under the Trust Indenture Act of 1939. The first mortgage bonds of all series that may be issued under the mortgage indenture are referred to in this prospectus as “first mortgage bonds.” The following summaries of certain provisions of the mortgage indenture do not purport to be complete and are subject to, and qualified in their entirety by, all provisions of the mortgage indenture and the first mortgage bonds.

The first mortgage bonds will be issued directly or as security for our obligations under the senior secured indenture and the senior secured debt securities issued thereunder. We refer to first mortgage