In October 1909, federal agents acting under the Pure Food and Drug Act seized forty barrels and twenty cans of Coca-Cola syrup in Chattanooga, Tennessee. The resulting court case, officially titled United States v. Forty Barrels and Twenty Cans of Coca-Cola, became one of the most famous legal actions in American history.
Dr. Harvey Washington Wiley, head of the Bureau of Chemistry, argued that Coca-Cola was adulterated because caffeine had been added as an 'injurious ingredient' and misbranded because the product no longer contained actual coca leaves or cola nuts in significant amounts. Coca-Cola countered that caffeine was a foundational component of its proprietary recipe rather than an added adulterant.
The legal battle raged all the way to the United States Supreme Court in 1916. Justice Charles Evans Hughes authored the opinion, ruling that added ingredients could indeed be deemed adulterants under the act, regardless of whether they were part of a secret formula. Rather than continue battling in lower courts, Coca-Cola struck a settlement with the government: the company agreed to reduce the amount of caffeine in its syrup by half and pay court costs, while the government dropped its remaining claims.
This precedent established modern FDA authority over food additives and secret corporate formulas.