To prevent spies from copying her fragrance formulas, Estée came up with an elaborate coding system for testing vials that was only known by “me, Joe and our sons.”

Perfume batches were produced only 95% complete, and then a member of the Lauder family would go in person to the factory before the fragrance was shipped out to retailers, “to supply the missing ‘secret 5%’–the ingredient without which the fragrance can never be complete,” Estée would explain. “The final ingredient is never known to our factories, essence suppliers, anyone,” she noted. “Only a Lauder knows.”