Answer:
principle owner
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Actually, that is not the correct answer.
"Principle" has one main meaning: "a law or rule".
"Principal" has more than half-a-dozen meanings, but typically is used to denote the "main" part of something (Principal Owner, Principal Offices, etc.).
And yes, it is possible to have rules that you might live by, and have ones among them that you consider most important. They would then be your "principal" (main) "principles" (rules, guidelines, or laws).
Therefore, you might be a "principled" (abiding by standards, rules, etc.) person that is the "principal" (main or primary) owner of a business.
Cheers!
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