52 Pa. Code § 1017.81
The following words and terms, when used in this subchapter, have the following meanings, unless the context indicates otherwise:
Fleet—A minimum of 25 taxicabs operated or owned by the same fleet owner.
Fleet owner—A sole proprietorship, corporation, partnership or limited liability company that owns or operates taxicabs and meets all of the following requirements:
(iii) Operates with a dispatcher who assigns drivers to fleet taxicabs.
Stand-by vehicle—A vehicle authorized by the TLD to provide temporary taxicab service and bearing a valid TLD issued inspection sticker in full compliance with TLD regulations. A stand-by vehicle is to be used only as a temporary replacement for a medallion taxicab that is temporarily out of service.