- Pabst Chemical Co., Chicago, Ill.2
- Porto Rican American Drug Co. (Inc.)2
- A. J. Fajardo, New York, N. Y.1
- A. Rodriguez, San Juan, P. R.1
- A. S. Wilson (Inc.)1
- Alferdo Ferran and Ramon Dapena, trading as Ferran & Dapena, Ponce, P. R.1
- American Rice Milling Co.1
- Ammonol Chemical Co.1
- Antonio Guzman Rodriguez, proprietor of the Farmacia Guzman, Mayaguez, P. R.1
- Arecibo Drug Co.1
- B. A. Delgado Carbouell, New York, N. Y.1
- Bayer Co., Inc., New York, N. Y.1
- Bigas & Co.1
- Brewer & Co.(Inc.)1
- Brewer & Co., Inc.1
- Candelaria Packing House1
- Caribou Laboratories, Aguadilla, P. R.1
- Charles L. Huisking & Co.1
- Chas. L. Huisking & Co.1
- Cie de la Marque Confiant, Luie Carraton, owner1