From the 3D Warehouse policy page:
Rights granted to other end users of the Services. You give other end users of the Services a perpetual, sublicensable, irrevocable, worldwide, royalty-free, and non-exclusive license to reproduce, adapt, modify, translate, publish, publicly perform, publicly display and distribute Existing Geolocated Models, Existing Non-Geolocated Models, New Models and related content and derivative works thereof which you submit, post or display on or through, the Services
It would seem that locking models violates the terms of service of the 3D Warehouse. I wonder if there is any way to "unlock" models based on these terms?