Products
- Portland Airport Corporation (Maine)
- Portland and Rumford Falls Railway
- Portland and Rumford Falls Railway
- Portland and Rumford Falls Railway
- Portland and Seattle Railway Company
- Portland Railroad Company
- Portland Vancouver & Yakima Railway Company
- Porto Rico Telephone Company
- Post Combination Sewing Machine Company
- Potomac Oil Company
- Potomska Mills Corporation
- Pottsville Packers, Inc. (Basketball)
- Pottsville Packers, Inc. (Basketball)
- Poughkeepsie & Eastern Rail Road Co.
- Poughkeepsie Bridge Company
- Poughkeepsie City and Wappingers Falls Electric Railway Company
- Poughkeepsie, Hartford & Boston Railroad Company
- Power Authority of the State of New York
- Powertown Tire & Rubber Company
- Powertown Tire Corporation
- Powhatan Realty Company (Issued to Thomas Williams Mason Long)
- PPG Industries, Inc.
- Prairie Pipe Line Company
- Pratt & Whitney Company
- Pressed Steel Car Company, Inc.
- Prince Telephone Company
- Princess Iron Corporation
- Professional Health Services, Inc.
- Profit-Sharing Candy Mfg. & Retail Stores Company
- Projections De Luxe, Inc.
- Providence and Worcester Rail Road Company
- Prudence-Bonds Corporation
- PUB United Corp. (Pepsi, Rheingold)
- Public Stores Corporation
- Publicker Industries Inc. (Distilling Company)
- Publicker Industries Inc. (Distilling Company)
- Puerto Rico International Airlines, Inc.
- Puget Sound & Willapa Harbor Railway Company
- Puget Sound Power & Light Company
- Pullman Company
- Pullman Incorporated
- Pullman Incorporated
- Pullman Transport Leasing Company
- Pullman's Palace Car Company
- Pure Gasoline Company
- Quartz King Mining Co.
- Quartz King Mining Co.
- Quincy Mining Company
- Quinta Corporation
- R. E. Thompson Manufacturing Company
- R. E. Thompson Radio Corporation
- R. H. Macy & Co., Inc.
- R. H. Macy & Co., Inc.
- R. H. Macy & Co., Inc.
- R. J. Reynolds Tobacco Company
- R. L. Dollings Company
- Radio Corporation of America (RCA)
- Radio Corporation of America (RCA)
- Radio Corporation of America (RCA)
- Radio Corporation of America (RCA)
- Radio Corporation of America (RCA)
- Radio Telephone Company
- Radio-Keith-Orpheum Corporation
- Radio-Keith-Orpheum Corporation
- Radio-Keith-Orpheum Corporation
- Railway Supply Company
- Rainbow Luminous Products, Inc.
- Rainbow Luminous Products, Inc. cashed in on Black Tuesday 1929
- Rainier Golf and Country Club
- Raleigh and Gaston Rail Road Company
- Ralston Purina Company
- Ramada Inns, Inc.
- Ramada Inns, Inc.
- Raritan River Railroad Company
- Raritan River Railroad Company
- Rauch & Lang, Inc.
- Raver Film Corporation
- Ray Hercules Copper Company
- Ray Hercules Copper Company
- Rayette-Faberge, Inc.
- Rayonier Incorporated
- RCA Corporation (Rockefeller Center)
- Reading (Railroad) Company
- Reading (Railroad) Company
- Reading (Railroad) Company
- Reading (Railroad) Company
- Reading (Railroad) Company
- Reading Base Ball and Athletic Association (Coal Barons, Marines)
- Real Silk Hosiery Mills, Incorporated
- Red Hill Florence Mining Company
- Red Mountain Railroad, Mining and Smelting Company
- Reed Radio & Electric Company
- Reelcraft Pictures Corporation (Signed by R. C. Cropper)
- Reeves Broadcasting Corporation
- Reiter-Foster Oil Corporation
- Reliance Electric and Engineering Company
- Reliance Insurance Company
- Religious and Educational Motion Picture Society
- Remington Phonograph Company (Signed by Philo E. Remington)
- Reno Air