Company: AILIM
Filing Date: 2025-09-16
Form Type: 424B2
Source: 0001104659-25-090464
Chunk: 104

Company: Ameren Illinois Co
Filing Date: 2025-09-16
Form: 424B2
Chunk 104
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 in connection with the securities remarketed thereby.

Any underwriters, dealers or agents participating in the distribution of the securities may be deemed to be underwriters and any discounts or commissions received by them on the sale or resale of the securities may be deemed to be underwriting discounts and commissions under the Securities Act. Agents, dealers and underwriters may be entitled, under agreements entered into with us, to indemnification by us against certain liabilities, including liabilities under the Securities Act, and to contribution with respect to payments which the agents, dealers or underwriters may be required to make in respect of these liabilities. Agents, dealers and underwriters may engage in transactions with or perform services for us in the ordinary course of business.

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Unless otherwise indicated in the applicable prospectus supplement, we do not intend to list the securities described in this prospectus on a national securities exchange.

We may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be identified in the applicable prospectus supplement.

### LEGAL MATTERS
Morgan, Lewis & Bockius LLP, New York, New York, and Stephen C. Lee, Esq., our Vice President and Deputy General Counsel, will pass upon the validity of the offered securities for us. Certain legal matters will be passed upon for any underwriters, dealers, purchasers or agents by Pillsbury Winthrop Shaw Pittman LLP, New York, New York. Pillsbury Winthrop Shaw Pittman LLP represents certain of our affiliates from time to time in connection with various matters. All matters pertaining to our incorporation and all other matters of Illinois law relating to us will be passed upon by Mr. Lee. As to all matters based on the law of the State of Illinois, Morgan, Lewis & Bockius LLP will rely on the opinion of Mr. Lee. As to all matters based on the law