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CPC technology class · B42

B42F - Sheets Temporarily Attached Together

Sheets temporarily attached together; filing appliances; file cards; indexing. 359 US utility patents granted 2015–2025, with the leading assignees and year-by-year grant trajectory.

359
US patents granted
#3/5
in B42
8.6%
B42 class share
-64%
5-yr velocity

The verdict

According to USPTO PatentsView, Sheets Temporarily Attached Together ranks #570 of 670 CPC technology areas - 359 US patents granted since 2015, with recorded grant volume down 64% over five years.

#570
of 670 CPC technology areas
359
US patents granted, 2015–2025
Rtc Industries
leading assignee (43)
-64%
grant velocity, last 5 yrs

How B42F's grant cadence moved

Between 2020–2024, B42F recorded 91 grants versus 252 in 2015–2019 (-64% equal-window velocity). Across complete years, output peaked in 2016 at 64 grants and bottomed in 2024 at 10 (+540% peak-over-trough). Lead assignee RTC Industries, Inc. holds 12.0% of the class ; the top three share 29.0%.

Leaderboard read

B42F concentration, lead at 12.0%

RTC Industries, Inc. leads this historical grant record at 12.0% of B42F - us corporation assignees hold 80% of class grants (161 of 202). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.

Leader's share
12.0%

43 of 359 grants

Top three share
29.0%

of the class's recorded grants

Lead over #2
3

more grants than Acco Brands Corporation

Where B42F sits inside B42

Among 5 subclasses in B42 (BOOKBINDING; ALBUMS; FILES; Special Printed Matter), B42F ranks #3 and holds 8.6% of the parent class's 4,157 recorded grants. Sibling chips below are the other subclasses in the same parent class, not the nationwide volume/lead-share peers further down.

B42D 2,774 B42C 578 B42B 331 B42P 115

Rising assignees active in B42F

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. #1 Acco Brands Corporation 0.80x 56 → 45 company-wide · 40 in B42F
  2. #2 CCL Label, Inc. 0.80x 46 → 37 company-wide · 14 in B42F
  3. #3 Canon Finetech Nisca Inc. 0.43x 117 → 50 company-wide · 5 in B42F
  4. #4 RTC Industries, Inc. 0.40x 48 → 19 company-wide · 43 in B42F
  5. #5 R. R. Donnelley & Sons Company 0.30x 20 → 6 company-wide · 6 in B42F

B42F grants by year, peak 2016 (64)

US utility-patent grants per year in B42F, 2015–2025 - recent five years are down 64% versus 2015–2019.

020406080 20152016201720182019202020212022202320242025 9

Who leads B42F?

The 12 most active assignees in Sheets Temporarily Attached TOGETHER; Filing APPLIANCES; File CARDS; Indexing - wider bars mean more grants

patents

What this shows Rtc Industries is the most active filer in B42F, holding 43 of the 359 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 B42F
Rank Company Patents in B42F
#1 RTC Industries, Inc. 43
#2 Acco Brands Corporation 40
#3 The Smead Manufacturing Company 21
#4 World Wide Stationery Mfg. Co., Ltd. 16
#5 CCL Label, Inc. 14
#6 LSC Communications US, LLC 8
#7 Microdata Corporation 7
#8 R. R. Donnelley & Sons Company 6
#9 Canon Finetech Nisca Inc. 5
#10 Ferag AG 4
#11 Nisca Corporation 4
#12 Rocket Innovations, Inc. 3
#13 Information Planning & Management Service Inc. 3
#14 Chung TIN International, Inc. 3
#15 The Stanley Works Israel Ltd. 2
#16 King JIM Co., Ltd. 2
#17 Unibind Limited 2
#18 iMICRODATA Corporation 2
#19 Ideastream Consumer Products, LLC 1
#20 Gift Card Impressions, LLC 1

Footprint here vs. claim strategy

Each dot is a leading B42F 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 B42F assignees by class footprint. Bubble size = patents in B42F. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 510152025 01020304050 Patents in B42F Avg claims / patent (company-wide) Rtc IndustriesAcco BrandsThe Smead Manufacturin…World Wide Stationery…Ccl LabelLsc Communications UsMicrodataR R Donnelley & SonsCanon Finetech NiscaFeragNiscaRocket InnovationsInformation Planning…Chung Tin Internationa…
Top 14 B42F assignees by class footprint. Bubble size = patents in B42F. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Questions about B42F

Which company holds the most patents in B42F?
RTC Industries, Inc. leads B42F with 43 patents (12.0% of the subclass). By PatentsView assignee type, us corporations account for 80% of class grants.
Which B42F assignees grew fastest recently?
Among assignees with ≥5 grants in B42F, Acco Brands Corporation shows the highest company-wide grant multiple (0.80x: 56 grants in 2019–2021 → 45 in 2022–2024) while holding 40 patents in this subclass. Growth is company-wide, not class-only.
How does B42F compare inside parent class B42?
Inside B42 (BOOKBINDING; ALBUMS; FILES; Special Printed Matter), B42F ranks #3 of 5 subclasses by grant volume and holds 8.6% of the parent class total. The largest sibling is B42D (2,774 grants).

What to do with this data

B42F in context - here's where to go next.

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

Methodology - B42F figures are USPTO PatentsView granted-utility totals for this subclass (359 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.