That's what NDAs are for. Coke was able to protect their secret formula with NDAs and access restriction for over 100 years without any legal protection whatsoever.
That's the gamble of trade secrets: no legal protection, but you can keep your monopoly as long as you can keep the secret. If you want the government to defend your monopoly, you have to file a public patent as a price of entry.
The Industrial Espionage Act of 1996 upended that balance by legally protecting trade secrets. Now you can have a government-protected monopoly for all eternity, all you have to do is stick a "secret" label on your invention. Patents are entirely redundant in this new world of trade secret protection.
That's the gamble of trade secrets: no legal protection, but you can keep your monopoly as long as you can keep the secret. If you want the government to defend your monopoly, you have to file a public patent as a price of entry.
The Industrial Espionage Act of 1996 upended that balance by legally protecting trade secrets. Now you can have a government-protected monopoly for all eternity, all you have to do is stick a "secret" label on your invention. Patents are entirely redundant in this new world of trade secret protection.