I started my last company and grew it with $20,000 to $12 million in 10 years. And while I was in the early phases, I did put in on my resume..

So, I believe you should. If it is a registered business entity and you are working it, it is still what you are doing, regardless of revenue of the company. If you are performing the tasks in your position, it shows you have been attempting to launch as well as (hopefully) prevents any gaps in employment. It also shows a level of commitment to your venture.

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