I just bring it in and put it in my cube. I never asked, and no one ever complained. Actually, seeing it there has inspired others to consider commuting by bike.

If you work in a warehouse, a bike inside will look even less out of place than in a white-collar office. And I don't know your work environment, but I can't see someone thinking they can steal a bike out of the very building they work in. That would be ridiculous.