The phrase "sole founder" means that someone started a business or organization all by themselves, without any partners or co-founders. Full definition
Before joining Robly, Anthony was the sole founder and CEO of Relectric Supply, which he grew from $ 0 to $ 50 mm in revenues over 8 years and sold to Audax Group in 2011. (smallbusinessesdoitbetter.com)
As a sole founder, the opportunity cost of my time was just too great at the time. (inc.com)
As a sole founder who had only raised $ 4.5 million from outside investors, Cerilli suddenly became a very rich man. (businessinsider.com)