Today if such an inventor published his idea in a public journal before patenting it, the same thing would happen because it would be prior art. But in any cas

Today if such an inventor published his idea in a public journal before patenting it, the same thing would happen because it would be prior art. But in any case, patents are entirely unnecessary for a small inventor to sell his idea. Just create a contract with the company to sell the idea. Your side of the contract says that you promise that your process works according to the parameters of efficiency you say it does, and that you won't reveal it to anyone else. The company's side says he hands over 10 million dollars.