X0609 4 2026-10-06 0 0001441816 MongoDB, Inc. MDB 0001339247 Hazard Charles M Jr false C/O FLYBRIDGE CAPITAL PARTNERS 855 BOYLSTON ST, SUITE 1000 BOSTON MA 02116 1 0 0 0 1 Common Stock 2026-10-06 4 S 0 595 363.85 D 45237 D Common Stock 13995 I By Trust Common Stock 17500 I By Limited Partnership The transactions were pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person. These shares are held by The Narragansett Bay Childrens Trust (the "Trust"). The Reporting Person is the Trustee of the Trust and, as such, has the power to vote and dispose of the shares held by the Trust. The Reporting Person disclaims beneficial ownership of the shares owned by the Trust except to the extent of his pecuniary interest therein and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of these securities for purposes of Section 16 or for any other purpose. The Reporting Person was appointed as the manager and general partner of a family limited partnership that owns the reported securities. The Reporting Person disclaims beneficial ownership of the reported securities except to the extent of his pecuniary interest therein. /s/ Paul Johnston, Attorney-in-Fact 2026-10-08