CPC technology class · D21

D21H - Pulp Compositions

Pulp compositions; preparation thereof not covered by subclasses d21c or d21d; impregnating or coating of paper; treatment of finished paper not covered by class b31 or subclass d21g; paper not otherwise provided for. 4,080 US utility patents granted 2015–2025, with the leading assignees and year-by-year grant trajectory.

Compiled by PlainPatent · May 15, 2026

4,080
US patents granted: #1/7
in D21: 49.9%
D21 class share: +4%
5-yr velocity

The verdict

According to USPTO PatentsView, Pulp Compositions ranks #271 of 670 CPC technology areas - 4,080 US patents granted since 2015, with recorded grant volume up 4% over five years.

#271
of 670 CPC technology areas: 4,080
US patents granted, 2015–2025: The Procter & Gamble
leading assignee (301): +4%
grant velocity, last 5 yrs

How D21H's grant cadence moved

Between 2020–2024, D21H recorded 1,861 grants versus 1,796 in 2015–2019 (+4% equal-window velocity). Across complete years, output peaked in 2020 at 422 grants and bottomed in 2015 at 310 (+36% peak-over-trough). Lead assignee The Procter & Gamble Company holds 7.4% of the class ; the top three share 15.2%.

Leaderboard read

D21H concentration, lead at 7.4%

The Procter & Gamble Company leads this historical grant record at 7.4% of D21H - us corporation assignees hold 52% of class grants (1,394 of 2,703). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.

Leader's share: 7.4%
Top three share: 15.2%
Lead over #2: 119

Where D21H sits inside D21

Among 7 subclasses in D21 (PAPER-MAKING; Production OF Cellulose), D21H ranks #1 and holds 49.9% of the parent class's 8,169 recorded grants. Sibling chips below are the other subclasses in the same parent class, not the nationwide volume/lead-share peers further down.

D21C 1,427 D21F 1,255 D21B 452 D21G 371 D21D 314 D21J 270

Rising assignees active in D21H

Company-wide grant multiples (2022–2024 vs 2019–2021) among assignees with ≥5 patents in this subclass. Growth is company-wide; class patent counts are subclass-specific.

#1 Toppan Inc. 56x 0 → 56 company-wide · 6 in D21H
#2 SNF Group 15x 0 → 15 company-wide · 9 in D21H
#3 Ahlstrom OYJ 15x 0 → 15 company-wide · 6 in D21H
#4 Qilu University of Technology 12x 2 → 23 company-wide · 6 in D21H
#5 Borregaard AS 10x 1 → 10 company-wide · 7 in D21H

D21H grants by year, peak 2020 (422)

US utility-patent grants per year in D21H, 2015–2025 - recent five years are up 4% versus 2015–2019.

The Procter & Gamble

301
Kimberly-clark…

182
Stora Enso Oyj

138
Kemira Oyj

111
Gpcp Ip Holdings

102
Omya International

101
Ecolab Usa

64
Georgia-pacific…

59
International Paper

56
Solenis

53
Daio Paper

46
Upm-kymmene

46

What this shows The Procter & Gamble is the most active filer in D21H, holding 301 of the 4,080 patents in this class. Concentration at the top signals how contestable this technology area is for new entrants.

View data table

Top patent holders in CPC subclass D21H
Rank	Company	Patents in D21H
#1	The Procter & Gamble Company	301
#2	Kimberly-Clark Worldwide, Inc.	182
#3	Stora Enso OYJ	138
#4	Kemira OYJ	111
#5	Gpcp IP Holdings LLC	102
#6	Omya International AG	101
#7	Ecolab USA Inc.	64
#8	Georgia-Pacific Consumer Products LP	59
#9	International Paper Company	56
#10	Solenis Technologies, L.P.	53
#11	Daio Paper Corporation	46
#12	Upm-kymmene Corporation	46
#13	First Quality Tissue, LLC	44
#14	Nippon Paper Industries Co., Ltd.	43
#15	Eastman Chemical Company	41
#16	WestRock MWV, LLC	41
#17	OJI Holdings Corporation	39
#18	Fiberlean Technologies Limited	33
#19	GP Cellulose GmbH	30
#20	Mitsubishi Paper Mills Limited	25

Footprint here vs. claim strategy

Each dot is a leading D21H 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 D21H assignees by class footprint. Bubble size = patents in D21H. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Classes near D21H's 4,080-grant footprint

Nationwide nearest neighbors for D21H (#271 of 670 by volume ; lead share 7.4%) - not the D21 parent-class siblings above.

Nearest by grant volume

F17C 4,101 B62J 4,111 F01P 4,129 F23R 4,138

Nearest by lead-assignee share

B21J 7.4% B60J 7.4% G21D 7.4% G06F 7.4%

Questions about D21H

Which company holds the most patents in D21H?

The Procter & Gamble Company leads D21H with 301 patents (7.4% of the subclass). By PatentsView assignee type, us corporations account for 52% of class grants.

Which D21H assignees grew fastest recently?

Among assignees with ≥5 grants in D21H, Toppan Inc. shows the highest company-wide grant multiple (56x: 0 grants in 2019–2021 → 56 in 2022–2024) while holding 6 patents in this subclass. Growth is company-wide, not class-only.

How does D21H compare inside parent class D21?

Inside D21 (PAPER-MAKING; Production OF Cellulose), D21H ranks #1 of 7 subclasses by grant volume and holds 49.9% of the parent class total. The largest sibling is D21C (1,427 grants).

What to do with this data

D21H in context - here's where to go next.

The Procter & Gamble Company leads D21H with 301 grants in this class. See full portfolio
D21H ranks #271 of 670 by grant volume among all tracked CPC technology areas. See the ranking
Inside parent class D21, the largest sibling subclass is D21C with 1,427 grants. Explore D21C

Figures reflect USPTO PatentsView grant data through 2026-05-15; pending applications not yet granted are not counted.

Methodology - D21H figures are USPTO PatentsView granted-utility totals for this subclass (4,080 grants in the tracked window).

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.