As per the general rule, every designated partner of an LLP must also be the partner of an LLP. However, there are some exceptions to the general rule:
If the partners of the LLP are a body corporate then in such case the nominees of the bodies corporate can act as a designated partner.
If the LLP agreement specifies certain persons to be a designated partners in an LLP without being a partner in the same LLP than such people can act as a designated partner.
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