Products
- Philadelphia Electric Company
- Philadelphia National Bank
- Philadelphia Rapid Transit Company
- Philadelphia Rapid Transit Company
- Philadelphia Rapid Transit Company
- Philadelphia Traction Company
- Philadelphia Traction Company
- Philadelphia Traction Company
- Philadelphia Traction Company (Signed by George Widener)
- Philadelphia Traction Company (Signed by George Widener)
- Philadelphia Transportation Company
- Philadelphia, Baltimore and Washington Railroad Company
- Philadelphia, Baltimore and Washington Railroad Company
- Philadelphia, Pennsylvania
- Philadelphia, Pennsylvania (1855)
- Philadelphia, Reading and New England Railroad Company
- Philadelphia-Searchlight Gold and Copper Mining Company
- Philip Morris & Co. Ltd., Incorporated
- Philip Morris Incorporated
- Philip Morris Incorporated
- Philip R. Park, Inc. (California Kelp Farmer)
- Philippine Long Distance Telephone Company
- Philips Electronics and Pharmaceutical Industries Corp.
- Phillip Best Brewing Company
- Phillip Best Brewing Company
- Phillip Best Brewing Company (Signed by Frederick Pabst)
- Phillips Petroleum Company
- Phillips-Van Heusen Corporation
- PHL Corp., Inc.
- Phoenix Materials Corporation
- Phoenix Medical Company
- Photo-Machine Company
- Pickwick Airways, Inc.
- Pickwick Corporation
- Pickwick Corporation
- Pickwick Corporation
- Picture Machine Service Corporation
- Pictures-In-Motion, Inc.
- Piedmont Petroleum Products Company Limited
- Pig'n Whistle Corporation
- Pig'n Whistle Corporation
- Piggly Wiggly Western States Company
- Pikes Peak Tunnel Mining Railway
- Pillsbury Company
- Pillsbury Company
- Pilsen Lumber Company
- Pincher Creek Oil and Refining Company, Ltd.
- Pine Bush National Bank
- Pine Creek Railway Company (Signed by Chauncey DePew and William K. Vanderbilt)
- Pine Plains Bank
- Pioneer Gasoline Company
- Pioneer Steamship Company (Signed by Charles Hutchinson)
- Pittsburg Ice Company
- Pittsburg Traction Company
- Pittsburgh & Eastern Railroad Company
- Pittsburgh & West End Passenger Railway Company
- Pittsburgh & West Virginia Railway Company
- Pittsburgh - Des Moines Steel Company
- Pittsburgh and Lake Erie Railroad Company
- Pittsburgh and Lake Erie Railroad Company
- Pittsburgh and Lake Erie Railroad Company (Signed by Florence Adele Vanderbilt Twombly)
- Pittsburgh and Lake Erie Railroad Company (Signed by Hamilton McKown Twombly)
- Pittsburgh and West End Passenger Railway Company
- Pittsburgh Crafton and Mansfield Street Railway Company
- Pittsburgh Obispo Plantation Company
- Pittsburgh Plate Glass Company
- Pittsburgh, Allegheny and Manchester Traction Company
- Pittsburgh, Cincinnati, Chicago and St. Louis Railroad Company
- Pittsburgh, Cincinnati, Chicago and St. Louis Railroad Company
- Pittsburgh, Cincinnati, Chicago and St. Louis Railway Company
- Pittsburgh, Cincinnati, Chicago and St. Louis Railway Company
- Pittsburgh, Fort Wayne and Chicago Rail Road Company
- Pittsburgh, Fort Wayne and Chicago Railway Company
- Pittsburgh, Lisbon & Western Railroad Company
- Pittsburgh, Lisbon & Western Railroad Company
- Pittsburgh, Marion and Chicago Railway Company
- Pittsburgh, McKeesport and Youghiogheny Railroad Company
- Pittsburgh, McKeesport and Youghiogheny Railroad Company
- Pittsburgh, McKeesport and Youghiogheny Railroad Company
- Pittsburgh, McKeesport and Youghiogheny Railroad Company (Signed by Frederick W. Vanderbilt)
- Pittsburgh, Virginia and Charleston Railway Company
- Pittsburgh, Wheeling and Kentucky Railroad Company
- Pittsburgh, Youngstown & Ashtabula Railroad Company
- Pittsburgh, Youngstown & Ashtabula Railroad Company
- Pittsburgh, Youngstown & Ashtabula Railroad Company
- Pittsburgh, Youngstown & Ashtabula Railway Company
- Pittsburgh-Jerome Copper Company
- Pittston Candy Works
- Pizza Hut, Inc.
- Planet Hollywood International, Inc.
- Platt Music Company (California)
- Playboy Enterprises, Inc.
- Playboy Enterprises, Inc. (Willy Rey)
- Plays and Players (Philadelphia Theater Company)
- Plymouth Rock Mining Company
- Plymouth, Kankakee and Pacific Railroad Company (Signed by John Edgar Thomson)
- Pocono Manor Association
- Polaroid Corporation
- Pondera Milk Products Co.
- Port Dover and Lake Huron Railway Company