Abstract: The technology provides a seat release blocker that covers a seat release latching mechanism, where the latching mechanism would enable a passenger to fold down one or more seats of a vehicle. This can be particularly beneficial when the vehicle is operating in an autonomous driving mode, because certain areas within the vehicle may be restricted from passenger access. For instance, access to the trunk or cargo area may be limited to authorized service personnel. The seat release blocker includes a cover member that is fixedly secured to a seat such as a middle seat, using one or more fastener members such as a screw. Once the cover is releasably secured to the seat, the side of the cover with the fasteners may be completely or substantially covered by the side of an adjacent seat.