SCHEDULE 13D/A 0001508239 XXXXXXXX LIVE 47 Class A Common Stock, $0.0001 par value 05/30/2025 false 0001441683 03782L101 Appian Corporation

7950 Jones Branch Drive McLean VA 22102

Abdiel Capital (646) 496-9202 90 Park Avenue, 29th Floor Attn: Colin T. Moran New York NY 10016 0001508239 N Abdiel Qualified Master Fund, LP OO N E9 0.00 8061920 0.00 8061920 8061920 N 18.7 PN 0001362771 N Abdiel Capital, LP OO N DE 0.00 353801 0.00 353801 353801 N 0.8 PN 0001963356 N Abdiel Partners, LLC OO N DE 0.00 14670 0.00 14670 14670 N 0.0 OO 0001659179 N Abdiel Capital Management, LLC OO N DE 0.00 8415721 0.00 8415721 8415721 N 19.5 OO Rows 8, 10 and 11. Consists of 8,061,920 shares of Class A Common Stock held by Abdiel Qualified Master Fund, LP and 353,801 shares of Class A Common Stock held by Abdiel Capital, LP. 0001578684 N Abdiel Capital Advisors, LP OO N DE 0.00 8430391 0.00 8430391 8430391 N 19.5 PN IA Rows 8, 10 and 11. Consists of 8,061,920 shares of Class A Common Stock held by Abdiel Qualified Master Fund, LP, 353,801 shares of Class A Common Stock held by Abdiel Capital, LP. and 14,670 shares of Class A Common Stock held by Abdiel Partners, LLC. 0001659198 N Colin T. Moran OO N X1 0.00 8430391 0.00 8430391 8430391 N 19.5 IN Rows 8, 10 and 11. Consists of 8,061,920 shares of Class A Common Stock held by Abdiel Qualified Master Fund, LP, 353,801 shares of Class A Common Stock held by Abdiel Capital, LP. and 14,670 shares of Class A Common Stock held by Abdiel Partners, LLC. Class A Common Stock, $0.0001 par value Appian Corporation 7950 Jones Branch Drive McLean VA 22102 Reference is hereby made to the statement on Schedule 13D filed with the Securities and Exchange Commission by the Reporting Persons with respect to the Class A Common Stock of the Issuer on June 12, 2017, Amendment No. 1 thereto on June 27, 2017, Amendment No. 2 thereto on June 29, 2017, Amendment No. 3 thereto on July 3, 2017, Amendment No. 4 thereto on July 7, 2017, Amendment No. 5 thereto on July 12, 2017, Amendment No. 6 thereto on July 31, 2017, Amendment No. 7 thereto on October 26, 2017, Amendment No. 8 thereto on November 20, 2017, Amendment No. 9 thereto on November 30, 2017, Amendment No. 10 thereto on December 12, 2017, Amendment No. 11 thereto on December 15, 2017, Amendment No. 12 thereto on February 23, 2018, Amendment No. 13 thereto on March 20, 2018, Amendment No. 14 thereto on March 27, 2018, Amendment No. 15 thereto on April 25, 2018, Amendment No. 16 thereto on April 30, 2018, Amendment No. 17 thereto on August 3, 2018, Amendment No. 18 thereto on August 24, 2018, Amendment No. 19 thereto on October 5, 2018, Amendment No. 20 thereto on October 15, 2018, Amendment No. 21 thereto on October 31, 2018, Amendment No. 22 thereto on November 2, 2018, Amendment No. 23 thereto on December 17, 2018, Amendment No. 24 thereto on February 22, 2019, Amendment No. 25 thereto on September 9, 2019, Amendment No. 26 thereto on December 3, 2020, Amendment No. 27 thereto on February 1, 2021, Amendment No. 28 thereto on May 5, 2022, Amendment No. 29 thereto on May 9, 2022, Amendment No. 30 thereto on May 11, 2022, Amendment No. 31 thereto on May 25, 2022, Amendment No. 32 thereto on November 14, 2022, Amendment No. 33 thereto on January 19, 2023, Amendment No. 34 thereto on January 26, 2023, Amendment No. 35 thereto on October 6, 2023, Amendment No. 36 thereto on November 9, 2023, Amendment No. 37 thereto on December 14, 2023, Amendment No. 38 thereto on February 23, 2024, Amendment No. 39 thereto on July 9, 2024, Amendment No. 40 thereto on July 12, 2024, Amendment No. 41 thereto on July 24, 2024, Amendment No. 42 thereto on August 2, 2024, Amendment No. 43 thereto on August 15, 2024, Amendment No. 44 thereto on August 26, 2024, Amemndment No. 45 thereto on April 15, 2025 and Amendment No. 46 thereto on May 20, 2025 (as so amended, the "Schedule 13D"). This Amendment No. 47 thereto supplements and amends the statement on Schedule 13D. Terms defined in the Schedule 13D are used herein as so defined. This Schedule 13D is filed by and on behalf of (i) Abdiel Qualified Master Fund, LP; (ii) Abdiel Capital, LP; (iii) Abdiel Partners, LLC; (iv) Abdiel Capital Management, LLC; (v) Abdiel Capital Advisors, LP; and (vi) Colin T. Moran (each, a "Reporting Person" and collectively, the "Reporting Persons"). The agreement among the Reporting Persons to file jointly (the "Joint Filing Agreement") was filed as Exhibit A to the initial filing and an amendment to the Joint Filing Agreement was filed as Exhibit A to Amendment No. 34. For each Reporting Person: 90 Park Avenue, 29th Floor New York, NY 10016 Each of Abdiel Qualified Master Fund, LP, Abdiel Capital, LP and Abdiel Partners, LLC is a private investment vehicle, the principal business of which is to make investments. The principal business of Abdiel Capital Management, LLC is to act as the general partner of Abdiel Qualified Master Fund, LP and Abdiel Capital, LP. The principal business of Abdiel Capital Advisors, LP is to act as the investment manager of Abdiel Qualified Master Fund, LP, Abdiel Capital, LP. and Abdiel Partners, LLC. Colin T. Moran serves as managing member of Abdiel Capital Management, LLC and Abdiel Capital Partners, LLC, which serves as the general partner of Abdiel Capital Advisors, LP. and managing member of Abdiel Partners, LLC. For each Reporting Person: No For each Reporting Person: No Abdiel Qualified Master Fund, LP is a Cayman Islands limited partnership. Each of Abdiel Capital, LP and Abdiel Capital Advisors, LP is a Delaware limited partnership. Each of Abdiel Capital Management, LLC and Abdiel Partners, LLC is a Delaware limited liability company. Colin T. Moran is citizen of the United States. Not Applicable Not Applicable The information requested by this paragraph is incorporated herein by reference to the cover pages to this Amendment No. 47 to Schedule 13D. Percentage ownership is based on 43,140,083 shares of Class A Common Stock outstanding as of May 5, 2025, as reported in the Issuer's Report on Form 10-Q for the period ended March 31, 2025 filed with the Securities and Exchange Commission on May 8, 2025. The information requested by this paragraph is incorporated herein by reference to the cover pages to this Amendment No. 47 to Schedule 13D. Information with respect to all transactions in the Class A Common Stock effected by the Reporting Persons since the filing of Amendment No. 46 to Schedule 13D is incorporated herein by reference to Exhibit A hereto. Not Applicable Not Applicable Not Applicable Exhibit A - Transactions Effected since the filing of Amendment No. 46 to Schedule 13D Abdiel Qualified Master Fund, LP /s/ Colin T. Moran 06/03/2025 Abdiel Capital, LP /s/ Colin T. Moran 06/03/2025 Abdiel Partners, LLC /s/ Colin T. Moran 06/03/2025 Abdiel Capital Management, LLC /s/ Colin T. Moran 06/03/2025 Abdiel Capital Advisors, LP /s/ Colin T. Moran 06/03/2025 Colin T. Moran /s/ Colin T. Moran 06/03/2025