LYONS MARTIN J 4

What Happened

• Martin J. Lyons, Chairman, President & CEO of Ameren Corporation, disposed of a total of 54,972 shares in two transactions totaling about $6.19 million. On 2026-02-27, 28,154 shares were withheld/used to satisfy exercise price or tax obligations at $113.28 per share (proceeds/value shown: $3,189,285). On 2026-03-03, 26,818 shares were sold in an open-market transaction at $111.84 per share for $2,999,325. Both actions are sales (dispositions), not purchases.

Key Details

• Transaction dates and prices:
  • 2026-02-27: 28,154 shares @ $113.28 — $3,189,285 (listed as payment of exercise price or tax liability)
  • 2026-03-03: 26,818 shares @ $111.84 — $2,999,325 (open-market sale)
• Total shares sold: 54,972; total proceeds ≈ $6,188,610.
• Shares owned after the transactions: Not specified in this filing.
• Notable footnotes:
  • F1: Estimated share equivalents in the Ameren Savings Investment Plan as of Feb 28, 2026.
  • F2: Shares withheld by issuer to satisfy tax withholding from vesting of performance/restricted stock units.
  • F3: The March 3 sale was made pursuant to a pre-arranged Rule 10b5-1 trading plan.
• Filing timeliness: The Form 4 was filed on 2026-03-03 for a Feb 27 transaction; this filing is within the required two-business-day window (timely).

Context

• The Feb 27 entry reflects withholding of shares to cover taxes/exercise obligations (a routine net-share settlement), while the March 3 sale was executed under a Rule 10b5-1 plan (a pre-set trading arrangement). Such transactions are common for insiders managing tax liabilities or following pre-established selling plans and do not, by themselves, indicate the insider’s view of the company’s prospects.