M. O. S. Corporation v. John I. Haas Co., Inc.

Appellant, the holder of the patent in suit, appeals from a judgment in favor of appellee in an action for infringement. This is the second appeal in this case. In M. O. S. Corp. v. John I. Haas Co., 9 Cir., 1964, 332 F.2d 910 , we reversed a judgment in favor of appellee. We held that it was error for the trial court to apply the doctrine of file wrapper estoppel in deciding that the patent was not infringed. We did not rule on the validity of the patent. Upon remand, the trial court received additional evidence. It again found that the patent was not infringed, but did not pass upon its validity, although that question was expressly raised by appellee, was stated as an issue in the amended pretrial order, and was litigated. On the present appeal, we affirm, but on the ground that the patent is invalid, rather than that appellee did not infringe.

Ordinarily, we would confine ourselves to the grounds for decision acted upon by the trial court. The Supreme Court, however, has announced certain policies applicable to patent litigation that convince us that we should consider the validity of the patent in this case, even though the trial court did not pass upon the question,…