The fourth amendment requirement for a search warrant applies only to government-owned, contractor-operated companies or when a contract specifically makes the company an agent of the government. Defense contractors are usually considered private companies not bound by the fourth amendment. Still, private contractors are subject to civil liability when searches and seizures are not properly conducted. Potentially applicable intentional torts include battery, trespass to chattels, defamation, and false imprisonment. To avoid being charged with battery, search and seizure procedure should limit searches to containers, where possible. When individuals are searched, they should consent to the search beforehand. A contractor can post a notice regarding the company's search and seizure policy. This notice should be placed in clear view at all entrances. It should list items subject to search and say that consent to search is a requirement for entering and exiting the building. When the notice is properly posted, anyone who enters the facility has given an implied consent to a search. To avoid defamation, searches should not be conducted without probable cause, and the person conducting the search should not accuse someone of theft or espionage. Protection against the liability of false imprisonment or false arrest can be ensured by making clear to employees beforehand the procedures the company will follow if an employee refuses to consent to a search.