On March 6, 1899, Frederick Bayer & Co. was granted a patent for Aspirin, the brand name for acetylsalicylic acid, now the most common drug found in household medicine cabinets. Bayer lost the patent on Aspirin during World War I. Eventually the company name and trademarks for the U.S. and Canada were purchased by Sterling Products (later Sterling Winthrop). By 1994 Bayer was an independent company again, and bought back the patent on aspirin and other OTC drugs.
