US 9977519

US Patent 9977519, titled "Active pen with bidirectional communication," was issued to Wacom Co Ltd and lists inventors Jeff Lukanc, Kirk Hargreaves, David Sobel, and Joseph Kurth Reynolds. The patent was filed on February 19, 2016, and issued on May 22, 2018.

Abstract:
The patent describes a processing system for an input device. This system includes a sensor module and a determination module. The sensor module initiates a beacon period by broadcasting a beacon signal, which contains an upstream packet with a pen identification (ID), to multiple active pens. During this period, the sensor module receives downstream packets from active pen transceivers in different timeslots. The determination module generates the upstream packet for a specific active pen and determines an attribute of that pen based on its received downstream packet.

Plain-language overview of independent claims:

• Independent Claim 1: This claim describes a system that manages communication with multiple active pens. The system's "sensor module" sends out a "beacon signal" to all active pens. This beacon signal contains specific instructions (an "upstream packet") for a particular active pen, including its unique ID. After sending this, the system receives data packets ("downstream packets") from active pens during specific time slots. A "determination module" inside the system creates these instructions for the active pens and figures out what an active pen is doing (an "attribute") based on the data it sends back.

• Independent Claim 6: This claim outlines a method for an active pen. The pen receives a "beacon signal" from an input device. This beacon signal includes instructions (an "upstream packet") that tell the pen its ID, which time slot to use, and what frequency to use for communication. Once it receives these instructions, the active pen then transmits its own data ("downstream packet") back to the input device during its assigned time slot and using the specified frequency. This downstream packet includes information about the pen's button status.

• Independent Claim 12: This claim details a method for operating a processing system within an input device. The method involves initiating a "beacon period" by broadcasting a "beacon signal" to multiple active pens. During this period, the system receives a first data packet ("first downstream packet") from a first active pen at a certain time and frequency, and a second data packet ("second downstream packet") from a second active pen at a different time and frequency. The system then determines an attribute of the first active pen using the information from its received data packet.

Uncertainty Note:
As of the current date, May 24, 2026, US Patent 9977519 is "Active" and is scheduled to expire on July 16, 2036. The patent family is currently involved in litigation. Specifically, a PTAB case (IPR2025-01533) was filed, though it was "Not Instituted - Procedural". There is also a US case filed in the Texas Eastern District Court (2:24-cv-00702) and a "First worldwide family litigation filed". The search for CAFC 2026 dockets did not return specific case information related to patent 9977519, only general information on how to access case records.