Less than one percent of petitions for inter partes review (“IPR”) involve design patents.  This is not surprising, as over 9,000,000 United States utility patents have issued compared to only about 735,000 design patents.  Several recent developments in design patent law, however, may narrow the gap as applicants look for less expensive ways to enhance their portfolios. Design Patent V2 For example, U.S. design patents filed on or after May 13, 2015 enjoy a 15-year term with no maintenance fees.  And U.S. design patent applicants may now file their design applications under the Hague Agreement, which publish six months after filing.
In some instances, design patent owners can seek pre-grant damages back to the date of that publication.  As design patents grow in popularity, so too will PTAB challenges to the validity of those design patents.  But challenging design patents can be very different from challenging utility patents.

As design patents grow in popularity, so too will PTAB challenges to the validity of those design patents.

The PTAB evaluates design patents in two nuanced ways: (1) claim construction, and (2) obviousness.  We get a glimpse of these nuances in Caterpillar, Inc. v. Miller International, Ltd., IPR2015-00416 (July 9, 2015). In Caterpillar, the PTAB granted a petition to institute IPR against design patent D673,982, “Operator-Visible Warning Symbol on a Coupler.”

Federal Circuit cases typically recommend construing design patent claims with reference to an illustration rather than a written description.  Egyptian Goddess, Inc. v. Swisa, Inc., 543 F. 3d 665, 679 (Fed. Cir. 2008) (en banc).  In Caterpillar, however, the PTAB found it helpful to describe in words certain features of the claim.  IPR2015-00416, *6 (describing Figs. 1-7 as “[a]n equilateral triangle with rounded corners and a horizontal base that is shaped as if projected onto a laterally extruded ‘S’-shaped surface”).  This approach is consistent with other PTAB design patent decisions.  See, e.g., Dorman Products, Inc. v. PACCAR, Inc., IPR2014-00555 (Sept. 5, 2014).  While the PTAB may not rule out the possibility of an essentially “wordless” claim construction that only refers to the illustrations in an IPR of a design patent, the trend is for the PTAB to adopt a construction that verbalizes various features.

Another peculiarity of design patent PTAB review is the obviousness analysis.  For design patents, “[t]he ultimate inquiry is ‘whether the claimed design would have been obvious to a designer of ordinary skill who designs articles of the type involved.’”  Caterpillar, IPR2015-00416, Slip Op. *7 (quoting Apple, Inc. v. Samsung Elecs. Co., Ltd., 678 F.3d 1314, 1329 (Fed. Cir. 2012) (internal quotation omitted).  This is a two-step test referred to as the Durling test:

  1. Identify a primary reference (otherwise known in design patent obviousness parlance as a Rosen reference). In re Rosen, 673 F.2d 388, 391 (CCPA 1982). A Rosen reference must have design characteristics that are basically the same as the claimed design.  To determine whether this threshold is met, it is necessary to “(1) discern the correct visual impression created by the patented design as a whole; and (2) determine whether there is a single reference that creates basically the same visual impression.”  Id. (quoting High Point Design LLC v. Buyers Direct, Inc., 730 F.3d 1301, 1311-12 (Fed. Cir. 2013)(internal quotation omitted).
  2. The primary reference can be modified by one or more secondary references to create a design having the same overall visual appearance as the claimed design, provided the secondary references are so related to the Rosen reference that the appearance of certain ornamental features in the secondary reference(s) would suggest the application of those features to the Rosen reference.

See Durling v. Spectrum Furniture Co., 101 F.3d 100, 103 (Fed. Cir. 1996).

In Caterpillar, the PTAB was asked to apply an obviousness test from Smith v. Whitman Saddle Co., 148 U.S. 674, 679 (1893) instead of the Durling test.  The PTAB declined, finding that the Supreme Court’s KSR Int’l Co. v. Teleflex, Inc., 550 U.S. 398 seminal obviousness decision has not been found applicable or germane to design patents.  IPR2015-00416, *9.

In applying Durling, the PTAB found that the proffered main reference, a Coupler Manual, was a suitable Rosen reference.  IPR2015-00416, *10.  And the secondary references were adequate to establish a reasonable likelihood that the petitioner would prevail in showing obviousness.

Caterpillar provides an example of the PTAB’s roadmap to determining whether to grant or deny a petition for IPR of a design patent, including guidance on the oddities of design patent claim construction and obviousness.  By faithfully navigating their way through the Durling test, petitioners and respondents will have some insight into what issues the PTAB will find most critical in deciding whether to institute IPRs of design patents.