The researcher individuals will be paid their salary and their jobs' existence depends solely on ability of the shareholders to protect their investment.
Exactly, and that's my point! The individual who does the invention gets a normal salary which they would've gotten anywhere doing anything (or, at best, a slightly higher salary than others doing similar work), and the people who reap the reward are the shareholders and executives.
That's worse an understanding of economics than I'd expect here. The fact that fruit of research and development is protected investment creates research jobs. Without patent protection, shareholders and executives would hire fewer people and overall progress would be slower.
But they are, even if it's not as direct as you like. The company/inventor is the patent holder, which benefits the inventor either directly or indirectly.
You're making it out like the individuals do not benefit from company's success. I'm saying that's not true, the continued existence of the company is a benefit to the individual.
The individual benefits a teeny tiny little bit from the company's success, but the individual is not getting rich from it. The idea that the inventor is significantly enriched by the patent system is a fantasy; the reality is that the inventor maybe has a slightly higher salary than they otherwise would, while the investors and executives are enriched. I don't know how many times I need to say this before it sinks in.