By 1899, Bayer's trademark Aspirin was registered worldwide for Bayer's brand of acetylsalicylic acid, but because of the confiscation of Bayer's US assets and trademarks during World War I by the United States – and the subsequent widespread usage of the word to describe all brands of the compound —, "Aspirin" lost its trademark status in the United States, France, and the United Kingdom. It is now widely used in the US, UK, and France for all brands of the drug. However in over 80 other countries, such as Canada, Mexico, Germany, and Switzerland, it is still a registered trademark of Bayer.
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