Joining Castings to Sheet Structures Patents: Top Companies & Trends 2026
- 54.7% concentration. The five leading assignees hold 47 of the 86 records in scope, a tight cluster around fastener and forging claims.
- Fasteners dominate the claim space. F16B fastener claims appear in 54.7% of records and B21J forging/hammering claims in 31.4%, far ahead of welding or alloy classes.
- Filing growth is negative on the last clean span. From 2021 to 2024 — the most recent years not distorted by publication lag — filings fell 33%.
Filing growth compares 2021 (3 records) with 2024 (2) — a three-year span. 2024 is the most recent year we treat as complete: publication lags filing by roughly 18 months, so 2025 onwards are still filling in and any growth rate that ends there would understate the field. Top-5 share is the combined record count of the five largest assignees divided by all 86 records in scope (CR5), not by the ranked leaders only.
What this landscape covers
Joining a casting to a sheet-metal or composite structure is a persistent mechanical problem in vehicle body engineering: the two parts have different stiffness, different corrosion behaviour, and often need to be serviced separately. The patent activity in this dataset clusters around three mechanical answers to that problem — self-piercing rivets, rivet bonding (a rivet combined with a cured adhesive layer), and dissimilar-material joining more broadly, with claims frequently touching galvanic corrosion control, joint fatigue, and tolerance stack-up between the mating parts.
The 86 records in scope span receiving offices led by the United States, with meaningful volume at the EPO, WIPO/PCT and in Japan. The IPC composition is fastener-heavy rather than materials-heavy: F16B and B21J together account for more filing activity than the alloy (C22C) or welding (B23K) classes, which tells a would-be filer that the contested ground is mechanical joint design, not the metallurgy of the casting itself.
Filing trend and technology composition
Two views of the same 86 records: how filing activity has moved year over year, and which IPC subclasses carry the claims.
Filing trend, 2017-2026
Filings ran from 2 in 2017 to a peak of 4 in 2022, then fell to 2 in 2024 — a 33% drop over the 2021-2024 span. 2025 and 2026 are still filling in under the roughly 18-month publication lag, so the apparent tail-off in the newest years should not be read as the technology cooling.
IPC subclass composition
F16B (fasteners) leads at 54.7% of the 86 records, with B21J (forging & hammering) second at 31.4%. B32B (laminates) and B62D (motor vehicles) tie at 18.6%, and alloy claims under C22C sit at just 8.1% — a record can carry several classes, so these shares add to more than 100%.
Shares are the percentage of the 86 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Joining Castings to Sheet Structures with Eureka
This page is one run against one query. Ask Eureka your own question about joining castings to sheet structures and every answer comes back with the patent numbers behind it.
Try EurekaThe most-cited prior art and a representative recent filing
US20190240723A1 — Rivet Bonding Workpiece Stack-Ups Having One Or More Polymer Composite Workpieces
A method of rivet bonding a workpiece stack-up that includes one or more polymer composite workpieces, such as carbon fiber composite workpieces, involves several steps. In one step, adhesive is applied to a surface of the workpiece stack-up. In another step, workpieces—including the polymer composite workpiece(s)—are brought together. In yet another step the adhesive is partially or more cured. A rivet is installed through the workpiece stack-up and through the adhesive in another step. The method strengthens the resulting rivet-bonded joint by minimizing or altogether precluding fracture, cracking, and/or delamination thereat.Filed by GM Global Technology Operations LLC, published 2019-08-08.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | US4988230A | Extruded node | 81 |
| 2 | US5059056A | Extrdued node | 80 |
| 3 | US5226696A | Motor vehicle chassis | 69 |
| 4 | US7001097B2 | Tubular joint assembly | 50 |
| 5 | US20090188100A1 | Chassis and methods of forming the same | 39 |
| 6 | US3603650A | Wheel liners for track-type vehicle | 37 |
| 7 | US5466035A | Improved vehicle front-end support structure for a passenger car | 33 |
| 8 | US20090188101A1 | A Method and Apparatus For Joining Metal Using Self-Piercing Rivets With Preheating | 32 |
| 9 | US20130266770A1 | Method and apparatus for joining parts to be joined which are subject to tolerance | 24 |
| 10 | US8234770B2 | Method and apparatus for joining metals using self-piercing rivets with preheating | 24 |
Citation counts favour older filings simply because they have had longer to accumulate citations inside this searched corpus — read them as a signal of influence on later filers, not as a measure of current relevance.
Each row carries its publication number; clicking a row searches Eureka by that number.
Put your own technology through the same analysis
Eureka on the web
When you want the answer in the next five minutes.
The agent works the prompt against patents and technical literature, citing every source.
Run your analysis now →MCP server & REST API
When it has to run inside your own pipeline.
Patent search, landscape analysis and assignee resolution as MCP tools. Drop them into any agent framework, or call REST directly.
Browse MCP servers →What the numbers mean for a filing decision
Three read-outs from the dataset that matter more than the raw counts on their own.
The top of the field is tight
Five assignees account for 47 of the 86 records in scope, and the top ten extend that to 69.8%. A newcomer is not entering an open field at the fastener-and-rivet core — it is entering a space where a handful of established filers already hold dense claim coverage.
Mechanical joint design, not metallurgy, is the contested ground
F16B and B21J together outweigh the alloy and welding classes by a wide margin. Filers competing on casting alloy chemistry (C22C, 8.1%) are working in a much less crowded corner than filers competing on the rivet or forming step itself.
Growth has slowed on the last clean data
The 2021-2024 span, the most recent period not distorted by publication lag, shows filings falling from 3 to 2 — a 33% decline. That is a signal to watch rather than a verdict on the field's future, since 2025-2026 volumes are still arriving.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to joining castings to sheet structures, with the prior art for and against each one.
| Assignee | Co-assignee | Shared families |
|---|---|---|
| Alcoa Inc | LONG RUSSELL S | 5 |
| Alcoa Inc | KLINGENSMITH JAMES D | 5 |
| Alcoa Inc | BANTHIA VINOD K | 5 |
| LONG RUSSELL S | KLINGENSMITH JAMES D | 5 |
| LONG RUSSELL S | BANTHIA VINOD K | 5 |
| KLINGENSMITH JAMES D | BANTHIA VINOD K | 5 |
| Industrial Origami Inc | GRECO MARIO | 3 |
| Industrial Origami Inc | HOLMAN RICK A | 2 |
Only 10 co-assignee pairs appear across the dataset, and the strongest of them share the same lead filer paired with different named inventors — evidence of one company's internal inventor teams rather than cross-company collaboration.
Who holds the ground, and where it opens up
The leading assignee sits well ahead of the rest of the ranked field, with a long tail of single- and few-filing entrants below tenth place.
One filer well ahead of the pack
The top-ranked assignee holds 16 of the 86 records, more than three times the count at fifth place (5). That gap is unusually wide for a field this size and suggests one company built an early, broad position around rivet and rivet-bonding claims.
A shallow drop-off after the leader
Filing counts fall off quickly after the top few names, from 5 records at fifth place to 2 at tenth. Below that the ranking becomes a long tail of individual inventors and smaller entities each holding a handful of records.
No leading assignee shows recent-year activity
Every one of the top-ranked assignees shows zero filings in the latest year of the dataset. Given the roughly 18-month publication lag, this is expected rather than a sign the leaders have exited the space — but it does mean the newest competitive moves are not yet visible in the public record.
| Assignee | Recent year | YoY |
|---|---|---|
| Textron Fastening Systems Ltd | 0 | — |
| GM Global Technology Operations LLC | 0 | — |
| Alcoa Inc | 0 | — |
| Magna International Inc | 0 | — |
| UT Battelle LLC | 0 | — |
| LONG RUSSELL S | 0 | — |
| KLINGENSMITH JAMES D | 0 | — |
| BANTHIA VINOD K | 0 | — |
Where to take this analysis
The figures here describe the shape of the field. Turning that into a filing or freedom-to-operate decision means going claim by claim against the leaders' actual grants.
Map claim scope against the leading assignees
The top five hold 54.7% of records; before filing near the fastener or rivet-bonding core, check exactly what those grants cover claim by claim.
Explore assignee claims in Eureka →Test a white-space claim before drafting
Under-claimed branches like corrosion-barrier interlayers or repairable rivet-bonded joints look open in the aggregate data, but that needs confirming against specific prior art.
Run a novelty check in Eureka →Track the newest filings as they publish
2025 and 2026 volumes are still filling in under the publication lag; set an alert rather than relying on a single snapshot.
Set up monitoring in Eureka →Common questions about this landscape
One assignee leads the ranked field with 16 of the 86 records in scope, well ahead of the fifth-place holder at 5 records. The top five assignees combined hold 47 records, or 54.7% of all records in scope, and the top ten extend that to 69.8%. Below the top ten the ranking becomes a long tail of 46 companies overall, many holding only one or two records, so the field is concentrated at the top but not closed off underneath it.
On the most recent clean comparison, 2021 to 2024, filings fell from 3 to 2 records, a 33% decline. Filing peaked so far in 2022 at 4 records. Because publication typically lags actual filing by around 18 months, the 2025-2026 figures in the dataset are still incomplete and should not be read as confirmation the field is shrinking further; they simply have not finished arriving yet.
Fastener claims under F16B are the largest single category, appearing in 54.7% of the 86 records in scope, with forging and hammering claims under B21J close behind at 31.4%. Layered-product claims (B32B) and motor-vehicle claims (B62D) each appear in 18.6% of records, while alloy composition claims under C22C appear in only 8.1%. Since a single record can carry several IPC classes, these percentages add up to more than 100% and should not be summed into a total.
That filing, from GM Global Technology Operations LLC and published in 2019, covers a method of rivet bonding a workpiece stack-up that includes at least one polymer composite workpiece such as carbon fibre composite. The method applies adhesive, brings the workpieces together, partially or fully cures the adhesive, and then installs a rivet through both the stack-up and the adhesive layer. The stated purpose is to reduce fracture, cracking or delamination at the joint, which makes it relevant to anyone combining a rivet step with a curing adhesive step on a composite or mixed-material stack.
The alloy composition class (C22C, 8.1% of records) and welding/brazing class (B23K, 9.3%) carry noticeably less filing density than the fastener and forging classes that dominate the field. Specific branches such as corrosion-barrier interlayers between dissimilar metals, tolerance-stack compensation designed into the joint itself, and repairable rivet-bonded joints intended for service disassembly are not heavily represented among the most-cited or highest-volume filings. Any of these is a more open starting point than filing directly against the fastener-design core where the leading assignees already hold dense coverage.
Research Joining Castings to Sheet Structures in depth with Eureka
Go past this page: query the whole joining castings to sheet structures corpus yourself, in your own scope.
Every answer comes back with patent numbers you can open.
Disclaimer. This page is generated from Patsnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing on this page constitutes an exhaustive prior-art, novelty, freedom-to-operate, or validity search, nor does it constitute legal, financial, investment, or professional advice, and it should not be relied upon as such. Any patent, commercial, or strategic decision should be verified independently and reviewed with qualified patent, legal, and domain professionals. Patsnap makes no warranties, express or implied, as to the accuracy, completeness, or fitness for any particular purpose of the information presented.
Machine translation. Assignee and organisation names originally recorded in Chinese, Japanese or Korean have been rendered into English by an AI translation step so that the tables stay readable. These renderings are best-effort and may not match a company’s registered English name; the original name is what the underlying patent record carries, and it is what any Eureka query launched from this page uses.