secret partner

So long as a secret partner keeps the fact of his membership from the public, of course he will not be sued as a member.

A secret partner is one who keeps the fact of his membership in the partnership from the public.

The term, dormant partner, is sometimes used synonymously with secret partner.

A member of a limited partnership can never be a secret partner, since the terms of a limited partnership must be published.

His old school friend, Ballantyne, forced into bankruptcy the printing firm in which Scott was a secret partner.