David S. Rosenblatt - Nov 24, 2025 Form 4 Insider Report for 1stdibs.com, Inc. (DIBS)

Role: Chief Executive Officer, Director
Signature: /s/ Melanie Goins, Attorney-In-Fact for David S. Rosenblatt
Stock symbol: DIBS
Transactions as of: Nov 24, 2025
Transactions value $: -$448,914
Form type: 4
Date filed: 11/26/2025, 09:12 PM
Previous filing: Sep 10, 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
ROSENBLATT DAVID S	Chief Executive Officer, Director	300 PARK AVENUE SOUTH, 10TH FLOOR, NEW YORK	/s/ Melanie Goins, Attorney-In-Fact for David S. Rosenblatt	2025-11-26	0001237860

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	DIBS	Common Stock	Options Exercise	$2.58M	+667K	+36.12%	$3.87	2.51M	Nov 24, 2025	Direct
transaction	DIBS	Common Stock	Sale	-$3.03M	-595K	-23.68%	$5.09	1.92M	Nov 24, 2025	Direct	F1
holding	DIBS	Common Stock						22.5K	Nov 24, 2025	By 2024 Laura Thalheimer Rosenblatt Family Trust effective 4/1/2024
holding	DIBS	Common Stock						665K	Nov 24, 2025	By 2012 David Rosenblatt Family Trust dtd 11/30/2012

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	DIBS	Employee Stock Option (right to buy)	Options Exercise	$0	-667K	-100%	$0.00	0	Nov 24, 2025	Common Stock	667K	$3.87	Direct	F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	The transactions reported herein represent a net exercise of outstanding stock options. The reporting person received 666,666 shares of common stock on a net exercise of an option to purchase 666,666 shares of common stock. The Issuer withheld 595,071 shares of common stock underlying the option for payment of the aggregate exercise price of $2,579,997.42 and to meet the tax withholding obligations of the reporting person, using the stock price on November 24, 2025 of $5.09, pursuant to the terms of the 2011 Stock Option and Grant Plan.
F2	Option vests over four years with 1/48th of the shares vesting on each monthly anniversary of November 1, 2015, subject to the reporting person's continued service with the Issuer through the applicable vesting date.

Content

The transactions reported herein represent a net exercise of outstanding stock options. The reporting person received 666,666 shares of common stock on a net exercise of an option to purchase 666,666 shares of common stock. The Issuer withheld 595,071 shares of common stock underlying the option for payment of the aggregate exercise price of $2,579,997.42 and to meet the tax withholding obligations of the reporting person, using the stock price on November 24, 2025 of $5.09, pursuant to the terms of the 2011 Stock Option and Grant Plan.

Option vests over four years with 1/48th of the shares vesting on each monthly anniversary of November 1, 2015, subject to the reporting person's continued service with the Issuer through the applicable vesting date.