The trial court held that defendant has a complete affirmative defense in bar of plaintiff’s cause of action. We agree.

Under the policy, McNamér was required to notify Rural Mutual immediately of any claim or suit brought against him and forward the process received by him. Upon his death, that duty devolved upon his personal representative, upon whom the counterclaim was served. Failure to comply with the terms of the policy was a breach of the insurance contract and relieved Rural Mutual of liability as to such •claim. Heimlich v. Kees Appliance Co. (1950), 256 Wis. 356, 41 N. W. (2d) 359, Anno. 18 A. L. R. (2d) 455; Al Shallock, Inc., v. Zurich General Accident & Liability Ins. Co. (1954), 266 Wis. 265, 63 N. W. (2d) 89.

There can be no doubt that Rural Mutual was prejudiced by failure of McNamer’s personal representative to give it notice of the counterclaim. It was not a party to *408that action; it was deprived of its right to defend against the counterclaim on the merits; it was afforded no opportunity to protect its interests.

Plaintiff urges that this is a separate and distinct action from the earlier McNamer Case and no claim is being made here on the basis of the pleadings in that action. The claim made in this case is, however, based upon McNamer’s alleged negligence, as was its claim in the earlier case. That issue was tried, the jury finding the deceased free from negligence as to position on the highway, the only question submitted as to McNamer. The jury found Dempsey causally negligent as to position on the highway and as to operating his vehicle while intoxicated. American, the defendant in that case, appealed on the questions of Dempsey’s negligence only. It presented no argument with respect to the finding on McNamer’s negligence. This court held the evidence insufficient to support the findings as to Dempsey’s negligence and ordered the complaint dismissed. Now American attempts to retry the issue of McNamer’s negligence in an action against his insurer on the identical cause of action it asserted by counterclaim in the previous case. Moreover, as the trial court observed, it could be reasonably inferred that American knew or should have known that Rural Mutual was the insurer of McNamer, but it did not seek to join the insurance company as a party defendant in the previous action.

The facts recited above as to the McNamer Case are unnecessary to a decision in this case except to show that the claim made by plaintiff in this action is the same claim it asserted in the previous case against McNamer’s personal representative. The bar to its cause of action now arises from its own failure to join Rural Mutual in the first instance and then pursue its claim on the previous appeal.

By the Court, — Judgment affirmed.

(dissenting). I cannot agree that there was such breach of condition on the part of the personal representative of the defendant’s insured, the deceased McNamer, as to relieve the defendant insurance company from all liability on the policy.

In the recent case of Kurz v. Collins (1959), 6 Wis. (2d) 538, 551, 95 N. W. (2d) 365, we held that a breach of condition of a policy of automobile liability insurance, in order to work an avoidance of the policy, must be material if the rights of an injured third party have intervened subsequent to the issuance of the policy. The chief factor to be considered in determining whether such a breach is material is whether prejudice has resulted to the issuing company.

Manifestly in the instant case no prejudice resulted to the defendant company by the failure of McNamer’s personal representative to promptly forward to it the counterclaim served in the former action. The jury in that action by their special verdict found that McNamer was not causally negligent. Such finding was not disturbed by either the trial court or this court on appeal. Apparently the counterclaim was not disposed of by any formal judgment which specifically alluded to it, either before or after the appeal. Therefore, whatever effect such jury finding with respect to McNamer’s freedom from causal negligence has in the instant action is unaffected by the fact that the defendant did not assume the defense of the counterclaim in the first action. However, the defendant has not seen fit to plead that such jury finding is conclusive in this action.

As pointed out in the majority opinion the defendant had received prompt notice of the accident and had made its own investigation. Therefore, the failure to have the counterclaim forwarded to it in no way has made it harder for the defendant to defend the instant action than if such counterclaim had been so forwarded.

*410The last paragraph of the majority opinion seems to hold that the plaintiff is now precluded from suing the defendant because of its failure to implead the defendant as a party in the first action. However, this is an issue entirely outside the pleadings in the trial court and this precludes the defendant from raising it on the appeal.