While territories can be lost by remaining offline due to unpaid taxes (Where do I check my territory status and balance? What happens if my balance runs out?) or they can be traded to other entities, static constructs may still be present on those territories.
The new owner of a territory can requisition any static construct present on his territory. Requisitioning will start a two-week window where the new territory owner must allow access to the static construct for the former owner and where the former owner of the static construct is able to remove that static construct by dismantling and removing it from the territory. If the static construct is still present after two weeks, its ownership will automatically be transferred to the new owner of the territory. Constructs on abandoned territories that haven’t been claimed by a new owner can’t be requisitioned though.