Mo. Rev. Stat. § 359.181: When person becomes limited partner — admission of additional limited partner.

1. A person becomes a limited partner on the later of:

(1) The date the original certificate of limited partnership is filed; or

(2) The date stated in the records of the limited partnership as the date that person becomes a limited partner.

2. After the filing of a limited partnership's original certificate of limited partnership, a person may be admitted as an additional limited partner:

(1) In the case of a person acquiring a partnership interest directly from the limited partnership, upon the compliance with the partnership agreement or, if the partnership agreement does not so provide, upon the written consent of all partners;

(2) In the case of an assignee of a partnership interest of a partner who has the power, as provided in section 359.431, to grant the assignee the right to become a limited partner, upon the exercise of that power and compliance with any conditions limiting the grant or exercise of the power.