0001515156-23-000058 DEFA14A 3 20230427 20230427 Advanced Emissions Solutions, Inc. 0001515156 2890 275472457 1231 DEFA14A 34 001-37822 23858199 8051 E. MAPLEWOOD AVE., STE 210 GREENWOOD VILLAGE CO 80111 720-598-3500 8051 E. MAPLEWOOD AVE., STE 210 GREENWOOD VILLAGE CO 80111 DEFA14A 1 ades-2023scheduledefa14axn.htm DEFA14A United States SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ______________________________________ SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) ______________________________________ Filed by the Registrant x Filed by a Party other than the Registrant ¨ Check the appropriate box: ¨ Preliminary Proxy Statement ¨ Confidential, for use of the Commission only (as permitted by Rule 14a-6(e)(2)) ¨ Definitive Proxy Statement x Definitive Additional Materials ¨ Soliciting Material Pursuant to §240.14a-12 Advanced Emissions Solutions, Inc. (Name of registrant as specified in its charter) (Name of Person(s) Filing Proxy Statement, if other than the Registrant) Check the appropriate box: x No fee required ¨ Fee paid previously with preliminary materials. ¨ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11. 1 -------------------------------------------------------------------------------- [[Image Removed: naa1a.jpg]] 2 -------------------------------------------------------------------------------- [[Image Removed: naa2a.jpg]] 3