Dowagiac Manufacturing Co. v. Minnesota Moline Plow Co.

Citations

• 235 U.S. 641
• 35 S. Ct. 221
• 59 L. Ed. 398
• 1915 U.S. LEXIS 1822

Syllabus

<p>Where a patent is infringed by selling machines embodying improvements covered by the patent and the value of the machines as marketable articles is attributable in part to the patented improvements and in part to unpatented parts or features, the profits arising from the infringing sales belong to the owner of the patent in so far as they are attributable to the patented improvements, and in so far as they are due to the other parts or features they belong.to the seller.</p> <p>Upon an accounting in a, suit for such infringement the commingled profits resulting from selling the machines in completed and operartive form should be separated or apportioned between what was covered by the patent and what was not covered by it.</p> <p>If the plaintiffs patent covered only a part of the infringing machine and created only a part of the profits, he is required to take the initiative in presenting evidence looking to an apportionment.</p> <p>In an apportionment of profits mathematical exactness is not in- . dispensable, reasonable approximation being- what is required, and it usually may be attained through the testimony of experts and persons informed by observation'and experience.</p> <p>The result to be accomplished by an apportionment is a rational separation of the net profits so that neither party may have what rightfully belongs to the other.</p> <p>Where damages are sought for infringing sales and it does not ap- . pear that the plaintiff thereby lost the sale of a like number of machines or of any definite or even approximate number, no adequate basis is laid for an assessment of damages upon the ground of lost sales.</p> <p>As the exclusive right conferred by a patent' is property and infringe- ■ ment of it is a tortious taking of a part of that property, the normal measure of damages is the value of what was taken; and this may be shown by proof of an established, royalty, if there be such, and, if not, by proof of what would have' been a reasonable royalty,