Today brings us our first major Federal Circuit design patent decision of 2014. In a case of first impression, the Federal Circuit held yesterday that the principles of prosecution history estoppel apply to design patents. Pacific Coast Marine Windshields Ltd. v. Malibu Boats, LLC, No. 2013-1199, 2014 WL 53904 (Fed. Cir. Jan. 8, 2014). However, the court reversed the district court’s summary judgment of non-infringement because the accused infringing design was not within the scope of the subject matter surrendered during prosecution, and therefore remanded for further proceedings.
You may recall that we previously discussed the district court’s decision in Pacific Coast Marine Windshields late in 2012. At the time, we predicted that prosecution history estoppel would become a valuable tool for defendants involved in design patent infringement litigation. In view of the Federal Circuit opinion, however, defendants will have a more difficult time showing that the accused design falls within the scope of the surrendered territory and is therefore immune to a patent holder’s assertion that the accused design is a colorable imitation of the claimed design.
The background for the case is discussed more thoroughly in our earlier post on the district court decision. Briefly, Pacific Coast accused Malibu Boats of infringing U.S. Design Patent No. 555,070 for a “Marine Windshield.” A figure from the ‘070 Patent appears below alongside an image of the accused Malibu product:
While the two designs share many similarities, they differ in that the ’070 Patent shows four circular vents at the corner, while the accused device shows three rectangular ones. Of course, as courts have long recognized, for a design patent to be infringed it is not necessary that the accused device reproduce all elements of the patented design, since under such a standard infringement would never be found. Instead, “any colorable imitation” of the design will also be found to infringe. See 35 U.S.C. § 289.
However, during prosecution of the ‘070 Patent, the applicant canceled a number of figures in response to a restriction requirement from the examiner, including a two-hole embodiment shown below.
The district court ruled that, under a theory of prosecution history estoppel, the accused Malibu windshield fell within the territory surrendered during the prosecution of the ‘070 Patent and therefore Pacific Coast was estopped from asserting that the accused device was a “colorable imitation” of its patented design.
The Federal Circuit notes that the concept of “colorable imitation” for design patents is analogous to the doctrine of equivalents for utility patents. Therefore, prosecution history estoppel, which limits the availability of the doctrine of equivalents for a party asserting a utility patent, also limits the availability of infringement under the theory of “colorable imitation” in a design patent context.
Having concluded that prosecution history estoppel applies to design patents, the court gives us a glimpse into the analysis that must then take place in a design patent context to determine whether a plaintiff is estopped from asserting that the defendant’s design is a colorable imitation.
Whether prosecution history estoppel bars the infringement claim turns on the answers to three questions:
- Whether there was a surrender;
- Whether it was for reasons of patentability; and
- Whether the accused design is within the scope of the surrender.
Applying these three questions to the case at hand, the court answered the first and second in the affirmative, but reversed the district court by finding that the accused design was not within the scope of surrender.
In finding that there was a surrender, the court noted that here, in response to the examiner’s restriction requirement, the applicant amended the claim by canceling figures associated with all but one of the patentably distinct groups of designs identified by the examiner – the four-hole embodiment – and striking references to alternate configurations from the text. It did not matter that the surrender involved cancelation rather than amendment. By removing broad claim language referring to alternate configurations and canceling the individual figures showing the unelected embodiments, the applicant narrowed the scope of its original application, and surrendered subject matter.
In finding that this surrender was for reasons of patentability, the court noted that this element will be satisfied whenever an amendment is made to secure a patent. The narrowing amendment need not be to avoid prior art, but a narrowing amendment made to satisfy any requirement of the Patent Act may give rise to an estoppel. In the design patent context, a surrender resulting from a restriction requirement invokes prosecution history estoppel if the surrender was necessary to secure the patent.
As to the third question, the court rejected the defendant’s assertion that the accused design was within the scope of surrender. The defendant’s theory was that in patenting a four-hole design while canceling the two-hole design, the patent holder surrendered the range of territory between the canceled design and the patented design, namely a design with three holes, such as the accused windshield.
The Federal Circuit rejected this argument, however, noting that while an amendment to a value in a utility patent claim surrenders the entire range between the original and amended value, the range theory is not applicable in the context of design patents where ranges are not claimed, but rather individual designs. Claiming different designs does not necessarily suggest that the territory between those designs is also claimed. The applicant surrendered the claimed design with two holes on the windshield corner post, but neither submitted nor surrendered any three-hole design.
Notably, having rejected the defendant’s range theory for determining the extent of the surrendered scope, the court fails to definitively replace it. One obvious candidate for measuring the scope of surrendered territory would be to define that scope as all colorable imitations of the canceled design figure. The court notes this alternative but did not yet accept it. The court reasoned that they need not decide, in this case, whether the scope of the surrender is measured by the colorable imitation standard because it was not necessary to resolve the case. After all, the patent holder never asserted that the accused device was a colorable imitation of the two-hole design, and the defendant positively disclaimed that the two-hole embodiment was a colorable imitation of its accused design.
So where are we left as a result of this case? We now know that the theory of prosecution history estoppel applies to design patents as a limit to the colorable imitation standard. We also know that cancelation of figures in response to a restriction requirement triggers prosecution history estoppel because it constitutes a surrender of territory for reasons of patentability. Moreover, we know that the range theory from utility patents for determining the scope of surrender does not apply to design patents. Finally, we have a strong hint from the Federal Circuit that the scope of surrender will extend to all colorable imitations of the canceled figure, yet no final determination on that matter.
As a result, design patent applicants must be more careful in handling prosecution to avoid being subject to prosecution history estoppel. Meanwhile, defendants will have to be more persuasive in showing that their accused device falls within the surrendered territory.