Neb. Rev. Stat. § 21-221

(MBCA 2.03) (a) Unless a delayed effective date is specified, the corporate existence begins when the articles of incorporation are filed. (b) The Secretary of State's filing of the articles of incorporation is conclusive proof that the incorporators satisfied all conditions precedent to incorporation except in a proceeding by the state to cancel or revoke the incorporation or involuntarily dissolve the corporation.