Everything they left behind.
Roughly seven metric tons of hardware now sits on the property, per a widely cited 2022 estimate. None of it was cleared with the owner. Almost none of it is coming back.
Under Property Rule 8, owners of items left on the property have 30 sols from the date of this notice to arrange collection. After that, items are classified as abandoned and become the property of the Owner. The Owner would prefer they be collected.
The property is not a package locker.
Between December 2022 and January 2023, Perseverance set ten sealed tubes down on the floor of Jezero Crater at a site its operators call Three Forks. The tubes contain rock and soil cored out of the property. They were placed there so that a future mission could come and take them off the property.
To be clear about what happened: someone drilled into the owner's land, packed up what they found, and left it by the door for a courier. No courier has been confirmed.
The Office has addressed this in Notice NOT-2026-002.