The purpose of this guide is to provide you with basic information about filing a utility patent application with the USPTO. Five different types of Utility Patents in Allegheny County.Under the utility patent process, a special type of application known as a provisional patent application is allowed. Stainless steel, also known as inox, corrosion-resistant steel (CRES), and rustless steel, is an alloy of iron that is resistant to rusting and corrosion. The Pennsylvania Railroad Company, also known as the "Pennsy", was an American Class I railroad that was established in 1846 and headquartered in Philadelphia.