PlainPatent

CPC technology class · H03

H03L - Automatic Control

Automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses. 6,701 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

6,701
US patents granted
H03
Parent CPC class
20
Active assignees
-10%
5-yr velocity

The verdict

Automatic Control ranks #215 of 670 CPC technology areas - 6,701 US patents granted since 2015, with filing down 10% over five years.

#215
of 670 CPC technology areas
6,701
US patents granted, 2015–2025
Seiko Epson
leading assignee (302)
-10%
filing velocity, last 5 yrs
Top assignee: Seiko Epson Corporation (302 patents)

CPC subclass H03L - AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES - covers 6,701 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records, within the broader CPC class H03 (ELECTRONIC CIRCUITRY). See our CPC classification guide for how the system works.

The competitive landscape in H03L is shaped by 20 distinct companies actively filing in this space. Seiko Epson Corporation leads with 302 patents, followed by Texas Instruments Incorporated at 269 grants and SK Hynix Inc. at 133.

Filing activity in H03L is down 10% over the past five years versus 2015-2019, a relatively steady filing pace. All counts come directly from USPTO PatentsView and reflect US granted utility patents only.

Is H03L innovation accelerating?

US utility-patent grants per year in H03L, 2015–2025 - recent five years are down 10% versus 2015–2019.

300400500600700800900 20152016201720182019202020212022202320242025 342

Who leads H03L?

The 12 most active assignees in AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES - wider bars mean more grants

patents

What this shows Seiko Epson is the most active filer in H03L, holding 302 of the 6,701 patents in this class. Concentration at the top signals how contestable this technology area is for new entrants.

Source USPTO PatentsView, granted utility patents As of 2015–2025 grant years
View data table
Top patent holders in CPC subclass H03L
Rank Company Patents in H03L
#1 Seiko Epson Corporation 302
#2 Texas Instruments Incorporated 269
#3 SK Hynix Inc. 133
#4 Rambus Inc. 121
#5 Silicon Laboratories Inc. 104
#6 Realtek Semiconductor Corp. 89
#7 NXP B.v. 82
#8 Renesas Electronics Corporation 75
#9 Mediatek Inc. 74
#10 Xilinx, Inc. 69
#11 Stmicroelectronics International N.v. 52
#12 Altera Corporation 51
#13 NXP USA, Inc. 49
#14 Analog Devices, Inc. 45
#15 Inphi Corporation 40
#16 Nihon Dempa Kogyo Co., Ltd. 40
#17 Skyworks Solutions, Inc. 39
#18 Kandou Labs Sa 39
#19 Socionext Inc. 37
#20 Ciena Corporation 36

About This Class

CPC subclass H03L belongs to class H03.

6,701 patents were granted in this class between 2015 and 2025.

20 companies actively patent in this space.

Classification System

Cooperative Patent Classification (CPC) is a hierarchical patent classification system used by the USPTO and EPO.

← All Technology Classes Technology Rankings →

Footprint here vs. claim strategy

Each dot is a leading H03L assignee, placed by how many patents it holds in this class (horizontal) against its company-wide average claims per patent (vertical) - a read on whether the class is led by broad-but-shallow filers or focused deep-claim players.

Top 14 H03L assignees by class footprint. Bubble size = patents in H03L. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Top 14 H03L assignees by class footprint. Bubble size = patents in H03L. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 10152025 0100200300400 Patents in H03L Avg claims / patent (company-wide) Seiko EpsonTexas Instruments Inc…Sk hynixRambusSilicon LaboratoriesRealtek SemiconductorNxp B VRenesasMediatekXilinxStmicroelectronics In…AlteraNxp UsaAnalog Devices
Top 14 H03L assignees by class footprint. Bubble size = patents in H03L. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class H03L?
CPC subclass H03L covers AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES. It belongs to CPC class H03 (ELECTRONIC CIRCUITRY), with 6,701 US utility patents granted since 2015.
How many patents have been filed in H03L?
6,701 US utility patents were granted in CPC subclass H03L between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in H03L?
Seiko Epson Corporation leads H03L with 302 patents, making it the most active assignee in this technology area.
How is patent data for H03L collected?
Patent data comes from USPTO PatentsView, a public research dataset maintained by the United States Patent and Trademark Office. It covers all US granted utility patents and assigns CPC codes based on the technology described in each patent.
What is the difference between CPC class and subclass?
A CPC class (e.g., H03) is a broad technology category. Subclasses like H03L provide finer granularity within that category. PlainPatent organizes data at the subclass level (4-character codes) for the most useful view of technology domains.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from USPTO PatentsView - official U.S. government patent data. See our methodology for computation details. Retrieved and formatted by PlainPatent Editorial

Every figure on PlainPatent is rendered directly from USPTO source data, no number is typed in by an editor. This page draws directly on USPTO source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.