We see many companies with extremely high valuations like Microsoft, Google, Amazon etc. All these companies are held publicly. (Although the founder might be holding a large portion of the shares; I am not asking about that.)
In the past, these companies invented something and needed huge money to implement it on large scale. So they went public; sold their equity to others, and their valuations grew big.
But could there be a case where a company invents something which is much more valuable and in-demand. The founder invests their own money and does not sell their equity. Assume that they already have all the money necessary, or the company does not need much money at all to implement the invention in production, or the company implements the invention in production on a small scale first and grows in size by investing the profits back, or... etc.
My question is:
- Is this scenario practically possible? Are there any examples?
- Are there any legal restrictions that mean companies have to go public after certain stage?
Although I mentioned "legal restrictions", I am not looking for country-specific scenario.