Yes. WinCo and Nelson, acting on behalf of KD Concrete (the assumed business name of KDN), entered into a contract no later than mid-January, when they agreed to the material terms of the contract. It is undisputed that Nelson did not incorporate KDN until February 18. All persons purporting to act as or on behalf of a corporation, when there was no incorporation, are jointly and severally liable for all liabilities created while so acting. Because KDN was not incorporated until after the contract with WinCo was formed, Nelson was jointly and severally liable with KDN under the theory of pre-incorporation liability.