144 0001336088 XXXXXXXX LIVE 0001600641 1stdibs.com, Inc. 001-40453 51 Astor Place 3rd Floor New York NY 10003 212-627-3927 Thomas Etergino Chief Financial Officer Common CARTA SECURITIES LLC

333 Bush Street 23rd Floor, Suite 2300 San Francisco CA 94104

30928 110412.96 39509346 06/08/2023 NASDAQ Common 06/08/2023 RSU Vest 1stdibs.com, Inc. N 30928 06/08/2023 Common received upon vest of RSUs Y 06/06/2023 /s/ Melanie Goins, Attorney-In-Fact for Thomas J Etergino