| Level | Code | Display | Definition | 
 | 1 | AB | Abbott Laboratories (includes Ross Products Division) | Abbott Laboratories (includes Ross Products Division) 
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 | 1 | AD | Adams Laboratories | Adams Laboratories 
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 | 1 | ALP | Alpha Therapeutic Corporation | Alpha Therapeutic Corporation 
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 | 1 | AR | Armour [Inactive - use CEN] | Armour [Inactive-use CEN] 
 | 
 | 1 | AVI | Aviron | Aviron 
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 | 1 | BA | Baxter Healthcare Corporation | Baxter Healthcare Corporation 
 | 
 | 1 | BAY | Bayer Corporation (includes Miles, Inc. and Cutter Laboratories) | Bayer Corporation (includes Miles, Inc. and Cutter Laboratories) 
 | 
 | 1 | BP | Berna Products [Inactive - use BPC] | Berna Products [Inactive-use BPC] 
 | 
 | 1 | BPC | Berna Products Corporation (includes Swiss Serum and Vaccine Institute Berne) | Berna Products Corporation (includes Swiss Serum and Vaccine Institute Berne) 
 | 
 | 1 | CEN | Centeon L.L.C. (includes Armour Pharmaceutical Company) | Centeon L.L.C. (includes Armour Pharmaceutical Company) 
 | 
 | 1 | CHI | Chiron Corporation | Chiron Corporation 
 | 
 | 1 | CON | Connaught [Inactive - use PMC] | Connaught [Inactive-use PMC] 
 | 
 | 1 | EVN | Evans Medical Limited (an affiliate of Medeva Pharmaceuticals, Inc.) | Evans Medical Limited (an affiliate of Medeva Pharmaceuticals, Inc.) 
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 | 1 | GRE | Greer Laboratories, Inc. | Greer Laboratories, Inc. 
 | 
 | 1 | IAG | Immuno International AG | Immuno International AG 
 | 
 | 1 | IM | Merieux [Inactive - use PMC] | Merieux [Inactive-use PMC] 
 | 
 | 1 | IUS | Immuno-U.S., Inc. | Immuno-U.S., Inc. 
 | 
 | 1 | JPN | The Research Foundation for Microbial Diseases of Osaka University (BIKEN) | The Research Foundation for Microbial Diseases of Osaka University (BIKEN) 
 | 
 | 1 | KGC | Korea Green Cross Corporation | Korea Green Cross Corporation 
 | 
 | 1 | LED | Lederle [Inactive - use WAL] | Lederle [Inactive-use WAL] 
 | 
 | 1 | MA | Massachusetts Public Health Biologic Laboratories | Massachusetts Public Health Biologic Laboratories 
 | 
 | 1 | MED | MedImmune, Inc. | MedImmune, Inc. 
 | 
 | 1 | MIL | Miles [Inactive - use BAY] | Miles [Inactive-use BAY] 
 | 
 | 1 | MIP | Bioport Corporation (formerly Michigan Biologic Products Institute) | Bioport Corporation (formerly Michigan Biologic Products Institute) 
 | 
 | 1 | MSD | Merck and Co., Inc. | Merck & Co., Inc. 
 | 
 | 1 | NAB | NABI (formerly North American Biologicals, Inc.) | NABI (formerly North American Biologicals, Inc.) 
 | 
 | 1 | NAV | North American Vaccine, Inc. | North American Vaccine, Inc. 
 | 
 | 1 | NOV | Novartis Pharmaceutical Corporation (includes Ciba-Geigy Limited and Sandoz Limited) | Novartis Pharmaceutical Corporation (includes Ciba-Geigy Limited and Sandoz Limited) 
 | 
 | 1 | NYB | New York Blood Center | New York Blood Center 
 | 
 | 1 | ORT | Ortho Diagnostic Systems, Inc. | Ortho Diagnostic Systems, Inc. 
 | 
 | 1 | OTC | Organon Teknika Corporation | Organon Teknika Corporation 
 | 
 | 1 | PD | Parkedale Pharmaceuticals (formerly Parke-Davis) | Parkedale Pharmaceuticals (formerly Parke-Davis) 
 | 
 | 1 | PMC | Aventis Pasteur Inc. (formerly Pasteur Merieux Connaught; includes Connaught Laboratories and Pasteur Merieux) | Aventis Pasteur Inc. (formerly Pasteur Merieux Connaught; includes Connaught Laboratories and Pasteur Merieux) 
 | 
 | 1 | PRX | Praxis Biologics [Inactive - use WAL] | Praxis Biologics [Inactive-use WAL] 
 | 
 | 1 | SCL | Sclavo, Inc. | Sclavo, Inc. 
 | 
 | 1 | SI | Swiss Serum and Vaccine Inst. [Inactive - use BPC] | Swiss Serum and Vaccine Inst. [Inactive-use BPC] 
 | 
 | 1 | SKB | SmithKline Beecham | SmithKline Beecham 
 | 
 | 1 | USA | United States Army Medical Research and Materiel Command | United States Army Medical Research and Materiel Command 
 | 
 | 1 | WA | Wyeth-Ayerst [Inactive - use WAL] | Wyeth-Ayerst [Inactive-use WAL] 
 | 
 | 1 | WAL | Wyeth-Ayerst (includes Wyeth-Lederle Vaccines and Pediatrics, Wyeth Laboratories, Lederle Laboratories, and Praxis Biologics) | Wyeth-Ayerst (includes Wyeth-Lederle Vaccines and Pediatrics, Wyeth Laboratories, Lederle Laboratories, and Praxis Biologics) 
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