PTAB

IPR2025-00363

iRhythm Inc v. Welch Allyn Inc

Key Events

Petition

petition

Title: Body-Worn Physiological Sensor
Brief Description: The ’422 patent discloses a body-worn physiological heart monitor constructed from two primary components: a disposable module with electrodes for patient contact and a reusable computation-communication module. The reusable module mechanically and electrically connects to the disposable part to receive physiological signals, perform real-time analysis, and transmit the results to a remote receiver.

Prior Art Relied Upon: Matsumura (Japanese Patent Publication No. 2004-121360).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that Matsumura, which discloses a "bioelectric potential detector" with a disposable bioelectrode pad and a reusable signal processor, teaches or renders obvious every limitation of the challenged claims. Matsumura’s device includes a disposable substrate with electrodes (conductive gels) and a reusable computation-communication module (signal processor) with a housing that attaches to the substrate via hooks. Petitioner contended that the claimed "flexible printed circuit board layer" was an obvious modification of Matsumura’s two separate pieces of conductive material.
- Motivation to Combine (for modification): A POSA would combine Matsumura’s separate conductive elements into a single, flexible printed circuit board layer using well-known techniques. This modification would simplify the design, making manufacturing and assembly easier and more cost-effective than cutting and coating two separate pieces of material.
- Expectation of Success: Creating conductive traces on a single flexible substrate using printing techniques was a common and predictable method in the art, ensuring a high expectation of success.

Prior Art Relied Upon: Jensen (Application # 2003/0149349) and Matsumura.
Core Argument for this Ground:
- Prior Art Mapping: Petitioner asserted that Jensen discloses a body-worn "smart patch" for physiological monitoring that includes a disposable sensor assembly and a reusable portion with processing electronics. Jensen teaches a flexible circuit assembly with sensor contacts (electrodes) and copper wiring (conductive traces) connected to a microcontroller and transmitter (computation-communication module) within a housing. Petitioner argued this base reference meets most claim limitations.
- Motivation to Combine: A POSA would combine Jensen with Matsumura for two primary reasons. First, to improve hygiene and patient safety, a POSA would adopt Matsumura’s design, which better insulates the reusable components from the patient’s skin using a multi-layer disposable pad. Second, to provide uninterrupted monitoring, a POSA would incorporate Matsumura’s superior waterproof structure, allowing the device to be worn continuously, even during showering, which was a limitation of Jensen’s design.
- Expectation of Success: Both references describe wearable ECG monitors with similar disposable and reusable components. Modifying Jensen’s patch to incorporate Matsumura’s established methods for improving hygiene and waterproofing was a predictable design choice that would have been implemented with a reasonable expectation of success.

Prior Art Relied Upon: Ozguz (Application # 2005/0096513) and Matsumura.
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that Ozguz discloses a thin, flexible, bandage-like bio-sensor module that meets nearly all limitations of the independent claims. Ozguz’s disposable sensor includes a flexible substrate made of an insulating material, a printed circuit board layer with metallization (conductive traces), electrodes, and an integrated computation-communication module (microprocessor and transmitter) housed within the sensor's layers.
- Motivation to Combine: While Ozguz teaches a largely disposable module, it suggests some components can be reused. A POSA would look to Matsumura to implement a known and reliable method for releasably attaching reusable and disposable parts, as recited in claims 5 and 17. Matsumura’s use of detachable hooks provides a simple mechanical solution to connect the reusable processor of an Ozguz-like device to the disposable electrode patch, thereby reducing cost and waste.
- Expectation of Success: Applying a common mechanical attachment method like the hooks taught by Matsumura to another wearable ECG monitor like Ozguz to facilitate the separation of reusable and disposable parts would have been a straightforward and predictable modification for a POSA.

Petitioner argued that discretionary denial under Fintiv is unwarranted because the co-pending district court litigation is in a very early stage, with no trial date set and minimal resources invested.
Petitioner further argued that denial under §325(d) is inappropriate. Although Jensen was listed in an Information Disclosure Statement (IDS) during prosecution, it was one of over 125 references and was never substantively addressed by the Examiner. The primary references for Grounds 1 and 3, Matsumura and Ozguz, were never presented to or considered by the Office.

Petitioner requests the institution of an inter partes review and the cancellation of claims 1-7, 9-12, and 14-20 of the ’422 patent as unpatentable.