Patent professionals often break down claim elements into smaller portions—whether for creating claim charts, mapping claims to prior art, or mapping them onto an allegedly infringing device. While this practice can be useful, it carries inherent risks: improperly dissecting claim elements can inadvertently alter their scope. Even small missteps can lead to unintended consequences, such as broadening or narrowing claim scope, weakening arguments, or missing critical nuances.
In a recent PTAB decision, the Board dissected a claim element in a way that facilitated affirming a rejection. However, this approach arguably overlooked aspects of the claim as written. The case was a Boeing application; Appeal 2024-000719, Application 17/026,435. Claim 1 on appeal is reproduced below:
A cart comprising:
an ultraviolet (UV) light array including UV lamps configured to emit UV light to sanitize a surface of a component;
a body that includes a mobile base and multiple interconnected rigid members supported by the mobile base, wherein the UV lamps are mounted to at least one of the rigid members;
actuators mechanically connected to the body, one or more of the actuators configured to move the at least one of the rigid members on which the UV lamps are mounted relative to the mobile base;
a control unit configured to generate control signals for controlling the actuators to move the UV light array along a cleaning path that follows a contour of the surface; and
an output device configured to indicate: (a) when the cart operates in an autonomous mode to alert individuals in a vicinity of the cart, and (b) when the cart operates in a semi-autonomous mode to provide instructions regarding operation of the cart.
At issue was the final limitation. The cited art did have an autonomous mode and a semi-autonomous mode, and different indications were made during each. However, none of the indications identified, or indicated, which mode was being carried out. Thus, Boeing likely believed they had good reason to take issue with the rejection. In their mind, the claim was directed to an approach with an output device that indicates an alert that the trolley is operating in autonomous mode, and likewise for the semi-autonomous mode.
However, due to the way in which the PTAB broke down and interpreted the claim, it was possible to read the claim onto the art. In particular, the following illustrates the PTABs approach:
The plain language of step (a) of the output device limitation of claim 1 contains only two requirements. First, the cart must be operating in autonomous mode. Appeal Br. 12. Second, the cart must alert individuals who are located in a vicinity of the cart. Id. We see nothing in the language of step (a) which requires any particular type of alert at all, much less requires that the alert specifically indicate that the cart is operating in autonomous mode.
Armed with this interpretation (and seemingly forgetting the “configured to indicate” before the (a) element), it was then easy to find these “two requirements” in the cited art because the reference had the mode, and alarms could be generated during that mode (for purposes other than indicating that the mode was occurring). And to put the icing on the cake, because Boeing summarized their argument as being that the prior art “fails to describe, teach or suggest any type of output device that indicates an alert that the trolley is operating in autonomous mode”, the PTAB could essentially ignore this distinction as it does not match the claim language. Namely, the claim does not specify that the output indicates “that” the device is operating in any particular mode.
Here Boeing did not address the claim construction in their briefs, which may have given the Board a freer hand in coming up with one. Also, changing language in the argument is a red flag and enabled the board to brush aside arguments easier since they didn’t exactly match the claim language.
Whenever claim elements are broken down into sub-elements, numerous risks arise, including:
Broadening Scope: By isolating individual terms or phrases, you may inadvertently introduce interpretations that are broader than the original claim language.
Narrowing Scope: Conversely, focusing too narrowly on a particular sub-element may strip away context that is critical to the claim’s intended scope.
Misrepresentation: Paraphrasing or rewording claim language can unintentionally alter the meaning, leading to flawed arguments or analyses.
Some Tips to consider:
Avoid Paraphrasing: avoid paraphrasing or rewording claim elements when making arguments or mapping claims. Instead, try to use the exact language of the claim whenever possible. If paraphrasing seems necessary to make your argument work, this could be a red flag indicating a need to reassess your position.
Cross-Check Against Original Language: Always cross-check broken-down elements against the original claim language to ensure fidelity. Consider whether the smaller portions retain the intended meaning and scope.
Point Out Missing Context: Highlight aspects of the claim language that might be overlooked or misinterpreted in the breakdown.
Breaking down claim elements is a common practice, but it must be done with care to avoid scope drift and misinterpretation. Be careful and stay on the lookout for scope drift.