144 0001940974 XXXXXXXX LIVE 0001288847 Five9, Inc. 001-36383 3001 Bishop Drive Suite 350 San Ramon CA 94583 925-201-2000 Panos Kozanian Officer Common Stock Morgan Stanley Smith Barney LLC Executive Financial Services

1 New York Plaza 8th Floor New York NY 10004

7008 329376.00 74219203 06/04/2024 NASDAQ Common 06/03/2024 Restricted Stock Units Issuer N 7008 06/03/2024 Not Applicable N Panos Kozanian

3001 Bishop Drive Suite 350 San Ramon CA 94583

Common 03/04/2024 8994 560506.08 Panos Kozanian

3001 Bishop Drive Suite 350 San Ramon CA 94583

Common 03/05/2024 2298 135972.66 06/03/2024 Panos Kozanian