Do you mean 20% ownership in the company? Why would you want to do that? The mere fact that some big company is considering you a threat validates the potential of your product/services. You just need to move forward to transform that potential into reality.

Sustainability could be achieved by being creative in your strategic process and model. Traction should be build with market than competition. Focus on customers and let your competitors focus on you.

If some established company is looking at you as a threat then the ball is in your court. Why do you want to lose the grip by not going solo.

Looking for anything specific? Feel free to reach out with more clarity.