PlainPatent

CPC technology class · E03

E03F - Sewers

Sewers; cesspools. 1,375 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

1,375
US patents granted
E03
Parent CPC class
20
Active assignees
+33%
5-yr velocity

The verdict

Sewers ranks #416 of 670 CPC technology areas - 1,375 US patents granted since 2015, with filing up 33% over five years.

#416
of 670 CPC technology areas
1,375
US patents granted, 2015–2025
Milwaukee Electric To…
leading assignee (37)
+33%
filing velocity, last 5 yrs
Top assignee: Milwaukee Electric Tool Corporation (37 patents)

CPC subclass E03F - SEWERS; CESSPOOLS - covers 1,375 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records, within the broader CPC class E03 (WATER SUPPLY; SEWERAGE). See our CPC classification guide for how the system works.

The competitive landscape in E03F is shaped by 20 distinct companies actively filing in this space. Milwaukee Electric Tool Corporation leads with 37 patents, followed by ZURN Industries, Llc at 25 grants and Advanced Drainage Systems, Inc. at 25.

Filing activity in E03F is up 33% over the past five years versus 2015-2019, a sharp acceleration suggesting an emerging or fast-moving technology area. All counts come directly from USPTO PatentsView and reflect US granted utility patents only.

Is E03F innovation accelerating?

US utility-patent grants per year in E03F, 2015–2025 - recent five years are up 33% versus 2015–2019.

50100150200 20152016201720182019202020212022202320242025 88

Who leads E03F?

The 12 most active assignees in SEWERS; CESSPOOLS - wider bars mean more grants

patents

What this shows Milwaukee Electric To… is the most active filer in E03F, holding 37 of the 1,375 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 E03F
Rank Company Patents in E03F
#1 MAG Aerospace Industries, Llc 26
#2 ZURN Industries, Llc 25
#3 Advanced Drainage Systems, Inc. 25
#4 BIO Clean Environmental Services, Llc 22
#5 Seescan, Inc. 21
#6 Ridge Tool Company 18
#7 Thermaco Incorporated 17
#8 Infiltrator Water Technologies, Llc 15
#9 Oatey Co. 13
#10 ACO Sevrin Ahlmann Gmbh & Co KG 13
#11 LMK Technologies, Llc 12
#12 Oldcastle Precast Inc. 11
#13 Waskey Bridges, Inc. 11
#14 Oldcastle Infrastructure, Inc. 11
#15 Ipek International Gmbh 11
#16 Watts Regulator Co. 9
#17 Hydro International Ltd 9
#18 Stormtrap, Llc 9
#19 Schluter Systems L.p. 8
#20 Contech Engineered Solutions Llc 8

About This Class

CPC subclass E03F belongs to class E03.

1,375 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 E03F 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 E03F assignees by class footprint. Bubble size = patents in E03F. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Top 14 E03F assignees by class footprint. Bubble size = patents in E03F. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 10152025 1015202530 Patents in E03F Avg claims / patent (company-wide) Mag Aerospace Industr…Zurn IndustriesAdvanced Drainage Sys…Bio Clean Environment…SeescanRidge ToolThermaco IncorporatedInfiltrator WaterOateyAco Sevrin Ahlmann &…LmkOldcastle PrecastWaskey BridgesOldcastle Infrastruct…
Top 14 E03F assignees by class footprint. Bubble size = patents in E03F. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class E03F?
CPC subclass E03F covers SEWERS; CESSPOOLS. It belongs to CPC class E03 (WATER SUPPLY; SEWERAGE), with 1,375 US utility patents granted since 2015.
How many patents have been filed in E03F?
1,375 US utility patents were granted in CPC subclass E03F between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in E03F?
Milwaukee Electric Tool Corporation leads E03F with 37 patents, making it the most active assignee in this technology area.
How is patent data for E03F 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., E03) is a broad technology category. Subclasses like E03F 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.