509.140. It shall be sufficient to aver the ultimate fact ofthe capacity of a party to sue or be sued or the authority of aparty to sue or be sued in a representative capacity or the legalexistence of a corporation or of an organized association ofpersons that is made a party. When a person desires to raise anissue as to the legal existence of any party or the capacity ofany party to sue or be sued or the authority of a party to sue orbe sued in a representative capacity, he shall do so by specificnegative averment, which shall include such supportingparticulars as are peculiarly within the pleader's knowledge.When a party so raises such issue, the burden of proof thereonshall be placed upon the opposite party.
(L. 1943 p. 353 ยง 45)