A cautionary tale for use of “the present invention” – Techtronic Industries, LTD v. ITC

My first thought when reading this case was doesn’t anyone else have a garage door that will not close even when there is nothing in the way?  Or that goes on psychotic ‘opening and closing’ benders for no apparent reason?  I can’t be the only one – clearly improved garage door openers are needed in the art.

In a whiplash inducing case, TechTronic vs ITC – Chamberlain intervenor, the Federal Circuit reversed the ITC’s claim construction, and thus it’s holding that Appellants imported garage door openers infringed the claims of US patent 7,161,319, owned by Chamberlain.  This was after the Commission reversed the ALJ that had held that Chamberlain had disavowed wall consoles lacking a passive infrared detector and that Appellant’s imported openers did not infringe the ‘319 patent.


Chamberlain owns the ‘319 patent, directed to improved garage door openers.  The ‘319 patent discloses that passive infrared detectors had been used in such openers, but typically in conjunction with the head unit, where they were not particularly effective.  The ‘319 describes the claimed improvement as the housing of the infrared detector in a wall control unit.  Claim 1 is illustrative:

  1. An improved garage door opener comprising

a motor drive unit for opening and closing a garage door, said motor drive unit having a microcontroller,

and a wall console, said wall console having a microcontroller,

said microcontroller of said motor drive unit being connected to the microcontroller of the wall console by means of a digital data bus.

Chamberlain filed a complaint with the Commission in July of 2016, alleging that the Appellants violated section 337(a)(1)(B) by importing openers that infringe the ‘319 patent, as well as US patents 7,339,336 and 7,196,611.

The only disputed term of the claims was “wall console.”  The ALG determined that the ‘319 patent describes its invention as superior detection based on the location of the passive infrared detector in the wall console, rather than in the head unit, and that the only described embodiment in the ‘319 patent describes this placement.  The ALJ thus construed the term “wall console” as requiring inclusion of a passive infrared detector, and granted Appellants SJ motion of noninfringement.

The Commission reviewed, and ultimately reversed, the ALJ’s order, concluding that while “the [‘319] specification describes the ‘principal aspect of the present invention’ as providing an improved [passive infrared detector] for a garage door opener,” (note to self – never say “the principal aspect of the present invention” in a patent application)  the specification disclosed other aspects of the invention and a patentee is not required to recite in each claim all features described as important in the written description (there goes that bell again).  In reaching its conclusion, the Commission took note of the fact that the claims of US Patent 6,737,968, also owned by Chamberlain and which issued from a parent application expressly located the detector in the wall console, thereby “demonstrating the patentee’s intent to claim wall control units with and without passive infrared detectors.”  Emphasis original, citing the Commission Opinion, 2017 WL 1119884, at *10.  On remand, and under the Commission’s construction, the ALJ duly found that Appellants infringed the ‘319 patent, a determination that the Commission adopted.  Commission Determination, 2018 WL 8519593, at *1.  The case was then appealed to the Federal Circuit.

Disavowal or no disavowal, that is the question

Appellants made one principal argument on appeal – that the Commission erred in reversing the ALJ’s claim construction because of Chamberlain’s disavowal of openers with wall consoles lacking infrared detectors.  In particular, Appellants point to the ‘319 patent’s consistent description of the invention as a wall console with a passive infrared detector – the sole described embodiment also describing this feature – and the patents description of detectors located in the head unit as suboptimal.  Appellants argued that under Poly-America, LP v. API Industries, Inc., 839 F.3d 1131 (Fed. Cir. 2016), also relied upon by the ALJ in the initial ruling favoring Appellants, such a fact pattern constitutes disavowal of claim scope.

For their part, Chamberlain argued that the specification described the invention more broadly – i.e., as “relating in general to moveable barriers” or to garage door openers with “passive infrared detectors associated with them.”  And also, that the patent disclosed another invention related to the programming of the microcontroller.  The Commission added that the claims of the ‘968 patent are expressly directed to garage door openers with passive infrared detectors in the wall console, thereby evincing the patentee’s intent to seek broader claims in the ‘319 patent, with no specified location for the detector.  Further, the Commission argued, there was no disavowal because “[n]owhere does the ‘319 patent state that it is impossible or even infeasible to locate a passive infrared detector at some other location.”

“It is axiomatic that, where the specification “describes ‘the present invention’ as having [a] feature,” that representation may disavow contrary embodiments”

The Federal Circuit agreed with Appellants that Chamberlain had disavowed coverage of wall consoles lacking a passive infrared detector, dispensing with each of the Appellants and Commissions arguments in turn.  With respect to the argument that the specification described the invention more broadly, the Federal Circuit stated:

…the specification, in each of its sections, discloses as the invention a garage door opener improved by moving the passive infrared detector from the head unit to the wall console.  It is axiomatic that, where the specification “describes ‘the present invention’ as having [a] feature,” that representation may disavow contrary embodiments.

Citing Poly-America, 839 F.3d at 1136.

Regarding Chamberlain’s assertion that the teaching of the programming of the microcontroller undermined the conclusion that the patent was limited to wall controllers having infrared detectors, the Federal Circuit again disagreed and said that this fact “in no way undermines the conclusion that the infrared detector must be on the wall unit.”  In fact, the Federal Circuit noted, this part of the ‘319 patent “never discusses programming the microcontroller or applying digital signaling techniques for any purpose other than transmitting lighting commands from the wall console.”  Slip Opinion, page 12, first paragraph.

Nor did the argument that the ‘319 patent failed to describe an alternate location of the detectors as impossible fare well with the Court:

Indeed, it is difficult to imagine a situation in which the Commission’s standard would be satisfied.  Here, the entire specification focuses on enabling placement of the passive infrared detector in the wall console, which is both responsive to the prior art deficiency the ‘319 patent identifies and repeatedly set forth as the objective of the invention.  Thus, the ‘319 patent disavows locating the detector elsewhere, even without an express concession to that effect.  Slip opinion, page 13.

Finally, the Court rejected the argument that the doctrine of claim differentiation necessitated the conclusion that the ‘319 patent was not limited to the location of the detectors in the wall units:

As Chamberlain notes, it previously obtained claims expressly locating the passive infrared detector in the wall console in the ‘968 patent.  But, as the Appellants respond, when later faced with an enablement rejection during prosecution of the ‘319 patent, Chamberlain identified as its enabling disclosure the wall console of the preferred embodiment, which contains a passive infrared detector….the fact that Chamberlain obtained more modest claims in its parent patent does no inoculate it from the specification’s disavowal.  See Retractable Techs., Inc. v. Becton, Dickinson & Co., 653 F.3d 1296, 1305 (Fed. Cir. 2011) (“[A]ny presumption created by the doctrine of claim differentiation ‘will be overcome by a contrary construction dictated by the written description of prosecution history.’” (quoting Seachange Int’l, Inc. v. C-COR, Inc., 413 F.3d 1361, 1369 (Fed. Cir. 2005)


1) Limit use of the phrase “the present invention.”  Consider use of “In embodiments,…” and include the language that all embodiments are combinable.

2) Consider MPEP 2123 in light of this case, and using the Court’s reasoning as a blueprint to argue against rejections based on that section, if the fact pattern permits.

3) When filing continuations in efforts to obtain broader claim scope, the doctrine of claim differentiation cannot be substituted for written description support.