The findings of the trial court determine that the duplicate copy of the lease as held by the landlord was the true agreement as made by the parties. This finding is amply sustained by the evidence. The result of such findings is that the lease, in the form held by the tenant Davidson, did not express the true agreement
and he did not in truth have the option as expressed in his copy of the lease. On the other hand, the plaintiff acquired the other duplicate copy evidencing the true agreement.
Defendant now says, since this difficulty is directly attributable to the acts of Thorbus, plaintiff's grantor, in putting this false lease in the hands of Davidson and then giving his written consent to its assignment to defendant, that the doctrine of estoppel should now protect him and that plaintiff should not be permitted to question the validity of the lease as held by him.
The general elements of estoppel have been well expressed by this court. Dimond v. Manheim, 61 Minn. 178, 63 N.W. 495. A person may be guilty of such culpable negligence as to invoke the doctrine of estoppel against him. Ward v. Dean, 69 Minn. 466,72 N.W. 710; 21 C.J. 1126; 10 R.C.L. 695. No estoppel arises where the conduct of the party sought to be estopped is due to ignorance founded upon an innocent mistake. 21 C.J. 1125; 10 R.C.L. 695. But, whether the conduct of plaintiff's grantor may be said to be negligence, we need not consider for the very simple reason that before defendant can successfully invoke estoppel by conduct he must show that he "has been led thereby to change his position for the worse." Dimond v. Manheim, 61 Minn. 178,181, 63 N.W. 495; Nell v. Dayton, 43 Minn. 242, 45 N.W. 229. 21 C.J. 1060, 1113, 10 R.C.L. 697; Board of Co. Commrs. v. Gray,61 Minn. 242, 63 N.W. 635; Macomber v. Kinney, 114 Minn. 146,155, 128 N.W. 1001, 130 N.W. 851; Purcell v. Thornton, 128 Minn. 255,150 N.W. 899. In this case the defendant has made no effort to show that he has been prejudiced or that he has in any way changed his position for the worse because of the facts involved. This cannot be presumed. It was a matter calling for proof, and in the absence of proof of this essential element of estoppel that remedy is not available to defendant.
Affirmed.