> For the complete documentation index, see [llms.txt](https://docs.sevenpens.com/drawtab/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sevenpens.com/drawtab/tech/wacom-patents.md).

# Wacom patents

## Overview

Wacom brought EMR technology to drawing tablets decades ago. In the process they held the original patents (long since expired) and have many new ones.

Wacom lists all their patents here: <https://www.wacom.com/en-us/patents>

## Key Wacom patents

If you have time for some technical reading, these patents below describe some key aspects of EMR technology.

* **US Patent 4,878,553 - POSITION DETECTING APPARATUS**
  * ([**LINK TO PATENT**](https://patents.google.com/patent/US4878553A/en))
  * Date Filed: 1987-09-14
  * Date of Patent: 1989-11-07
  * Status: EXPIRED
* **US Patent 4,999,461 - COORDINATES INPUT APPARATUS (**[**LINK TO PATENT**](https://patents.google.com/patent/US4999461A/en)**)**
  * Date Filed: 1989-05-19
  * Date of Patent: 1991-03-12
  * Status: EXPIRED
* **US Patent 5,134,689 COORDINATE INPUT SYSTEM AND INPUT IMPLEMENT USED IN THE SYSTEM**
  * [**LINK TO PATENT**](https://patents.google.com/patent/US5134689A/en)
  * Date Filed: 1988-08-24
  * Date of Patent: 1992-07-28
* **US Patent 5,691,513 SCANNING METHOD FOR SENSOR COILS IN COORDINATE DATA INPUT DEVICE**
  * [**LINK TO PATENT**](https://patents.google.com/patent/US5691513A/en)
  * Date Filed: 1995-09-25
  * Date of Patent: 1997-11-25
  * Status: EXPIRED
* **US Patent Reissue 4,786,765 COORDINATES INPUT SYSTEM**
  * [**LINK TO PATENT**](https://patents.google.com/patent/US4786765A/en)
  * Date Filed: 1987-07-23
  * Date of Patent: 1988-11-22
  * Status: Ceased
* **US Patent Reissue 5,023,408 ELECTRONIC BLACKBOARD AND ACCESSORIES SUCH AS WRITING TOOLS**
  * [**LINK TO PATENT**](https://patents.google.com/patent/US5023408A/en)
  * Date Filed: 1989-06-13
  * Date of Patent: 1991-06-11
  * Status: Ceased