PlainPatent

CPC technology class · F28

F28C - Heat-exchange Apparatus

Heat-exchange apparatus, not provided for in another subclass, in which the heat-exchange media come into direct contact without chemical interaction. 493 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

493
US patents granted
F28
Parent CPC class
20
Active assignees
+5%
5-yr velocity

The verdict

Heat-exchange Apparatus ranks #545 of 670 CPC technology areas - 493 US patents granted since 2015, with filing up 5% over five years.

#545
of 670 CPC technology areas
493
US patents granted, 2015–2025
Baltimore Aircoil
leading assignee (30)
+5%
filing velocity, last 5 yrs
Top assignee: Baltimore Aircoil Company, Inc. (30 patents)

CPC subclass F28C - HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA COME INTO DIRECT CONTACT WITHOUT CHEMICAL INTERACTION - covers 493 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records, within the broader CPC class F28 (HEAT EXCHANGE IN GENERAL). See our CPC classification guide for how the system works.

The competitive landscape in F28C is shaped by 20 distinct companies actively filing in this space. Baltimore Aircoil Company, Inc. leads with 30 patents, followed by Evapco, Inc. at 19 grants and SPX Cooling Technologies, Inc. at 17.

Filing activity in F28C is up 5% 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 F28C innovation accelerating?

US utility-patent grants per year in F28C, 2015–2025 - recent five years are up 5% versus 2015–2019.

203040506070 20152016201720182019202020212022202320242025 26

Who leads F28C?

The 12 most active assignees in HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA COME INTO DIRECT CONTACT WITHOUT CHEMICAL INTERACTION - wider bars mean more grants

patents

What this shows Baltimore Aircoil is the most active filer in F28C, holding 30 of the 493 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 F28C
Rank Company Patents in F28C
#1 Baltimore Aircoil Company, Inc. 30
#2 Evapco, Inc. 19
#3 SPX Cooling Technologies, Inc. 17
#4 THE Chemours Company FC, Llc 10
#5 Sdcmaterials, Inc. 9
#6 Prime Datum, Inc. 8
#7 Brentwood Industries, Inc. 7
#8 Prime Datum Development Company, Llc 7
#9 Ecovap, Inc. 7
#10 Energy And Environmental Research Center Foundation 6
#11 Koch-glitsch, Lp 5
#12 BOOZ Allen Hamilton Inc. 4
#13 OVH 4
#14 Gradiant Corporation 4
#15 Heatcraft Refrigeration Products Llc 3
#16 Inertech IP Llc 3
#17 Oy Halton Group Ltd. 3
#18 Ensyn Renewables, Inc. 3
#19 Munters Corporation 3
#20 Dri-steem Corporation 3

About This Class

CPC subclass F28C belongs to class F28.

493 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 F28C 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 F28C assignees by class footprint. Bubble size = patents in F28C. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Top 14 F28C assignees by class footprint. Bubble size = patents in F28C. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 01020304050 010203040 Patents in F28C Avg claims / patent (company-wide) Baltimore AircoilEvapcoSpx CoolingThe Chemours FcSdcmaterialsPrime DatumBrentwood IndustriesPrime Datum Developme…EcovapEnergy and Environmen…Koch-glitschBooz Allen HamiltonOvhGradiant
Top 14 F28C assignees by class footprint. Bubble size = patents in F28C. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class F28C?
CPC subclass F28C covers HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA COME INTO DIRECT CONTACT WITHOUT CHEMICAL INTERACTION. It belongs to CPC class F28 (HEAT EXCHANGE IN GENERAL), with 493 US utility patents granted since 2015.
How many patents have been filed in F28C?
493 US utility patents were granted in CPC subclass F28C between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in F28C?
Baltimore Aircoil Company, Inc. leads F28C with 30 patents, making it the most active assignee in this technology area.
How is patent data for F28C 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., F28) is a broad technology category. Subclasses like F28C 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.