FC Construes Claim, Holds “a” Means “one”

FC Construes Claim, Holds “a” Means “one”

Zero Spill Systems (Int’l) Inc. v. 614248 Alberta Ltd.2013 FC 616

This action concerns allegations of infringement of two Canadian Patents No. 2,258,064 (064 Patent) and No. 2,136,375 (375 Patent), and a Canadian Industrial Design No. 86793 (793 Design) all related to oil field fluid containment trays. The Plaintiffs allege that the Defendants have infringed the 064 Patent and the 375 Patent by manufacturing and/or selling competing oil field fluid containment products.  They also allege that one of the Defendants has infringed on the 793 Design by making and selling a product that is substantially similar in appearance.

The Defendants variously assert non-infringement and invalidity, and have counterclaimed for a declaration that the Plaintiffs’ Canadian Patent No. 2,166,265 (265 Patent) is invalid.

The 375 patent is valid, but not infringed.

The 064 patent is invalid (anticipation and obviousness), and in any event, not infringed.

The 793 design is valid, but not infringed.

The 265 patent is invalid (obviousness).


The 375 Patent – Construction

Claim 1 asserts a method for retrofitting an existing drilling rig with a catch tray, the design of which is directed at the capture and recirculation of drilling fluids that may spill from the wellhead during operation. Claim 2 covers the fluid containment apparatus. Claim 1 recites:

1.                  A method for retrofitting existing drilling rigs with a catch pan, comprising of the following steps:

            firstly, providing a pan-like body consisting of two portions, each portion including an interior edge having a semi-circular indentation with depending semi-cylindrical collar, the semi-cylindrical collars having interior surfaces, latching means being provided to secure the interior edges in abutting relation such that the semi-cylindrical collars mate to form a cylindrical collar with a cylindrical interior sealing surface; and

            secondly, providing an annular seal;

            thirdly, securing the annular seal to a flow nipple disposed below an opening in a drilling platform;

            fourthly, positioning the semi-circular indentations with depending semi-cylindrical collars on opposed sides of the flow nipple with the cylindrical interior sealing surface of the cylindrical collar engaging and being telescopically movable relative to the annular seal and using the latching means to secure the interior edges in abutting relation, such that drilling fluids from the drilling platform are caught in the pan-like body and directed into the flow nipple and as the drilling platform settles such settling is accommodated by movement of the cylindrical interior sealing surface of the cylindrical collar relative to the annular seal.

“[B]y choosing a particular means to accomplish the advantage of tray movement and to distinguish the invention from the prior art, it is not open to the Plaintiffs to stretch these claims to monopolize anything that may achieve the same result.” [76]

The Plaintiffs did argue that another essential element of the 375 Patent concerns its redirection of drilling fluid into the flow nipple. The Court disagreed, and noted that that feature was “very common in the upper containment trays that were in prior use.  It is only the presence of the telescopic seal that is arguably inventive and distinguishes the 375 Patent claims from what was long before in widespread use.” [77]

The 375 Patent – Validity

The Court held that the 375 Patent is not rendered invalid by anticipation or obviousness.

Do the Defendants’ Upper Trays Infringe the 375 Patent?

The Court held that the “Defendants’ systems for mounting their upper trays to a flow nipple of a drilling rig are sufficiently different from the considerably more elegant 375 Patent design that they do not infringe either of claims 1 or 2.” [104]

The 064 Patent – Construction

Claim 1 reads as follows:

1.         An oilwell leak containment apparatus for a completed oilwell, comprising:

a shallow tray-form body segmented into at least two segments, each of the at least two segments having a non-mating edge and a mating edge, the non-mating edge having an upstanding containment wall, when the at least two segments are coupled together to form the body the upstanding containment wall extending around a peripheral edge of the body and defining a liquid containment cavity, the mating edge mates with an other of the at least two segments, each mating edge having an arcuate portion, when the at least two segments are coupled together to complete the body the arcuate portions forming a circular collar adapted to be positioned around a christmas tree;

at least one of the two segments having a drainage aperture; and

couplers for clamping the mating edges together.

The Plaintiffs argued that despite the 064 Patent claim language describing a tray forming “a liquid containment cavity” capable of being drained by “at least one…drainage aperture”, claims 1 and 9 “should be broadly interpreted to include a design that incorporates two self-contained trays that do not seal at their abutting edges and that are separately drained.” [107]

“Claims 1 and 9 of the 064 Patent clearly describe a tray that is formed into one leak-proof containment cavity from two or more sections that are joined and coupled along their mated edges and that is capable of being drained with one aperture.” [110] The Court did not agree with the Plaintiffs that the use of the indefinite article “a” in this context should be interpreted to mean “one, some or any”.  “The drafter was careful to use the phrase ‘at least two’ in several places to describe the segments of the tray and would be presumed to intend the singular in the absence of that or a similar phrase.” [110] The Court distinguished Bell Express Vu on the basis of differing grammatical context.

The 064 Patent – Validity

The Court held that the 064 Patent was anticipated by two prior art patents, which “achieve the same purpose by exactly the same means.” [117] The 064 Patent was also anticipated by the prior use of similar systems within the industry.

Even if no exact replica of the 064 Patent apparatus was in prior use, the Court held that “there is nothing about the design or fit up of the 064 Patent lower tray that would not have been obvious to a person of skill long before the material date.” [118]

The 064 Patent – Infringement

Having regard to the construction of Claims 1 and 9, the Court found there was no infringement.

“The language of the 064 Patent claims is confined to the use of the apparatus on a developed oil well where the problem is one of leaking oil and not drilling fluids. It would not be an infringement of the 064 Patent claims for the Defendants to sell their containment products for use with an operating drilling or service rig. The uncontradicted evidence before the Court is that the Defendants have not offered their lower containment trays for use on completed oil wells and, apparently, neither have the Plaintiffs. Accordingly, there is no evidence of infringement by the Defendants with respect to the sale of these products.” [121]

The 793 Industrial Design – Line Pipe Trays

The Plaintiffs alleged that by making and marketing their visually-similar product, one of the Defendants has infringed their exclusive right and privilege in the 793 Design and they have suffered damages in the result. They also alleged that the Defendant’s 346 Design is invalid because it was known by the Defendant to be a copy of the Plaintiffs’ 793 Design. The Defendant pleaded that their competing product does not infringe the 793 Design.

The Court found that there was no evidence that the design features that are common to the Defendant’s product and the 793 Design are “anything other than functional”. [132] To the extent that there are any appealing visual aspects to the 793 Design, those are not duplicated by the Defendant’s product.  The Court found that the Plaintiffs have failed to prove infringement on a balance of probabilities.

The 265 Patent – Validity

The Court found that the 265 Patent is invalid on the ground of obviousness.


The authors believe this decision to be significant because patent drafters frequently assume that the use of the indefinite article “a” is grammatically equivalent to “at least one”. Indeed, drafters often feel compelled to shrink uses of the phrase “at least one” down to “a” in order to achieve elegance and concision in the claim draft.  Here is one example, however, where such an assumption was rejected by the Court.  At the same time the authors understand the Court’s construction because the element “a liquid containment cavity” appears at the conclusion of a number of structural elements to ultimately define “…. a liquid containment cavity”.  Accordingly the preceding structural language can be studied to discern the drafter’s intent that the structure was to define a single liquid containment cavity.  This distinguishes this case from other uses of nouns where the indefinite article “a” commences a claim phrase in order to introduce the subject of the claim phrase, the latter case being more normally associated with the equating of “a” to mean “at least one.”