Shot Peening Patents: Who Leads, Where the Gaps Are 2026
- Filing has cooled since its 2017 peak. 65 records that year fell to 28 by the 2022 midpoint and 4 in the most recent (partial) year — a flat-to-declining trend, not a growing one.
- The top 5 hold 35.5% of the field. 430 of 1,210 records in scope sit with five assignees, rising to 45.8% (554 records) once the top 10 are counted — concentrated, but with a long tail beneath.
- Heat treatment and abrasive blasting dominate the classification mix. C21D covers 58.8% and B24C covers 55.2% of the 1,210 records, while laser-shock-adjacent B23K sits at 16.7% — showing where claim space is dense and where it thins out.
What this landscape covers
This dataset tracks patent families filed against shot peening, laser shock peening and deep rolling where the claims or abstract reference compressive residual stress, Almen intensity, fatigue life improvement, coverage or surface roughness, restricted to IPC classes covering heat treatment, abrasive blasting and laser-based metalworking. The scope spans 2015 to a 2026-07-31 cut-off, and captures 1,210 published records.
Because publication typically lags filing by around 18 months, the most recent year in any trend understates true filing activity — the 2026 figure in particular should be read as incomplete rather than as a genuine collapse in interest.
Filing trend and technology composition
Two views of the same 1,210 records: how filing activity has moved year over year, and which IPC subclasses carry the claim density.
Filing trend, 2017–2026
Filing peaked at 65 records in 2017 and declined to a midpoint of 28 in 2022, with only 4 recorded in the most recent partial year. The pattern reads as flat-to-declining rather than an emerging technology still building momentum, though the final year or two will revise upward as later publications land.
IPC subclass composition
C21D (heat treatment of metals) and B24C (abrasive blasting) each cover more than half of the 1,210 records — 58.8% and 55.2% respectively — confirming these as the structural core of the field. B23K (welding/laser processes, 16.7%), C23C (coatings, 13.1%) and C22C (alloys, 10.0%) trail well behind, and F16F, C22F and B23P sit under 7% each, marking the field's thinner, more open branches. Records can carry multiple IPC codes, so these shares sum to well over 100%.
Shares are the percentage of the 1,210 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Shot Peening and Surface Strengthening with Eureka
This page is one run against one query. Ask Eureka your own question about shot peening and surface strengthening and every answer comes back with the patent numbers behind it.
Try EurekaRepresentative and most-cited records
Method and apparatus for providing a layer of compressive residual stress in the surface of a part (US7159425B2)
The shot peening method and apparatus described controls shot peening coverage to provide higher surface compression and comparable depth of compression to conventional 100% coverage peening, but with reduced cold working — improving thermal stability and cutting shot peening time and cost. The preferred embodiment uses x-ray diffraction residual stress measurement and percent cold work determined by line broadening to establish the optimal degree of coverage for a given material and peening intensity.Filed by Surface Technology Holdings, Ltd.; granted 2007-01-09.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | US5674328A | Dry tape covered laser shock peening | 158 |
| 2 | US5492447A | Laser shock peened rotor components for turbomachinery | 156 |
| 3 | US5756965A | On the fly laser shock peening | 144 |
| 4 | US5932120A | Laser shock peening using low energy laser | 142 |
| 5 | US5674329A | Adhesive tape covered laser shock peening | 134 |
| 6 | US5744781A | Method and apparatus for laser shock peening | 125 |
| 7 | CN101392382A | 一种激光熔覆结合激光喷丸强化表面改性的方法和装置 | 95 |
| 8 | US20050155203A1 | Method and apparatus for improving the magnitude of compressive stress developed in the surface of a part | 77 |
| 9 | US5596912A | Press plate having textured surface formed by simultaneous shot peening | 75 |
| 10 | US20170087670A1 | Method and Device for Implementing Laser Shock Peening or Warm Laser Shock Peening During Selective Laser Mel… | 69 |
Citation counts favour older filings simply because they have had more time to accumulate citations within the searched corpus — read them as a signal of influence on the field's early laser-shock-peening work, not as a measure of current relevance.
Patent titles are shown in the language they were filed in, not translated, so that each record stays verifiable against the original filing — a translated title will not match in Eureka or in any national register. Each row carries its publication number; clicking a row searches Eureka by that number.
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Reading the concentration, the technology mix and the citation record together points to a mature, well-occupied field with specific pockets still open.
The leadership tier is narrow
Five assignees account for 430 of the 1,210 records in scope, rising to 45.8% (554 records) across the top 10. That leaves more than half the field spread across a long tail of single- and few-filing entrants — dense at the top, fragmented below it.
Activity has cooled since 2017
The 2022 midpoint of 28 records sits well below the 2017 peak, and the trend has not recovered since. Read the final year cautiously — an 18-month publication lag means recent filings are still arriving.
Heat treatment claims dominate the field
C21D and B24C together anchor the vast majority of records, meaning most claim space around core coverage and residual-stress control is already occupied. The lighter-populated subclasses — F16F, C22F, B23P — are where structural claim density is thinnest.
Early laser shock peening patents still anchor prior art
The most-cited records in this corpus are laser shock peening patents from the 1990s, each cited well over 130 times. Any laser-shock-peening filing today has to work around this foundational cluster.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to shot peening and surface strengthening, with the prior art for and against each one.
Who is filing, and where momentum has gone quiet
The ranked leaders span automotive OEMs, turbine and heavy-industry manufacturers, and specialist laser-peening firms — but recent-year filing activity has slowed across nearly all of them.
A single leader well ahead of fifth place
The top assignee holds 122 records against 44 at fifth place and 18 at tenth — a steep drop-off that marks genuine leadership rather than a crowded top tier.
Recent-year activity has gone quiet at the top
Several of the most active historical filers show zero records in the latest tracked year, including major automotive and industrial names — consistent with the field-wide flat-to-declining trend rather than any one company's retreat.
Filing is mostly independent, with a few tight pairs
Only 10 co-assignee pairings appear in the data, and the strongest pairs link parent-subsidiary structures within the same corporate group rather than cross-company joint filings — collaboration outside a single group is rare here.
| Assignee | Recent year | YoY |
|---|---|---|
| Sintokogio, Ltd. | 0 | -100% |
| General Electric Co. | 0 | — |
| NHK Spring Co., Ltd. | 0 | — |
| Toyota Jidosha KK (Toyota Motor Corporation) | 0 | — |
| Nippon Steel Corporation | 0 | — |
| Mazda Motor Corporation | 0 | — |
| Toyota Motor Corporation | 0 | — |
| LSP Technologies, Inc. | 0 | — |
Where to take this next
The landscape points to a field with an occupied core and thinner edges — the next step is deciding where a specific claim would actually land.
Map a candidate claim against the cited cluster
Before drafting around coverage control or Almen intensity, check it against the small cluster of highly-cited 1990s laser shock peening patents that still anchor prior art in this space.
Explore prior art in EurekaWatch the quiet leaders for re-entry
Several top assignees show zero filings in the latest year despite large historical portfolios — a resumption of filing from any of them would be an early signal worth tracking.
Set up assignee tracking in EurekaTest the under-claimed branches
F16F, C22F and B23P carry far lower record counts than the C21D/B24C core — worth a freedom-to-operate check before assuming the space is open.
Run a white space search in EurekaCommon questions about shot peening patents
The ranking in this dataset covers 100 assignees, and the leader holds 122 records — well ahead of the fifth-place company at 44. The top 5 assignees together account for 35.5% of all 1,210 records in scope, and the top 10 account for 45.8%. Below that top tier, filing activity spreads across a long tail of companies with only a handful of records each, so the field is concentrated at the top but not dominated by a single monopoly.
Filing has slowed since a peak of 65 records in 2017, dropping to 28 by the 2022 midpoint and to just 4 in the most recent tracked year. That pattern reads as flat-to-declining rather than a technology on the rise. Because publication lags filing by roughly 18 months, the final year or two will likely revise upward as later filings publish, but the multi-year trend before that lag effect is genuinely downward.
This landscape is built around C21D (heat treatment of metals), B24C (abrasive blasting) and B23K (welding, soldering and laser processes, which captures laser shock peening). C21D and B24C are the largest, covering 58.8% and 55.2% of the 1,210 records respectively, while B23K covers 16.7%. Coating-related C23C and alloy-related C22C classes appear in a smaller but still notable share of records, reflecting overlap with surface treatment and materials science filings.
US7159425B2 describes a shot peening method and apparatus that controls peening coverage — rather than relying on conventional 100% coverage — to achieve comparable compressive stress depth with less cold working. It uses x-ray diffraction residual stress measurement and cold-work determination by line broadening to set the optimal coverage level for a given material and peening intensity. The claimed benefit is improved thermal stability and reduced peening time and cost, filed by Surface Technology Holdings and granted in 2007, making it a reference point for any coverage-optimisation claim in this space.
The classification data shows F16F (springs and vibration dampers), C22F (non-ferrous metal treatment) and B23P (general metal working) each cover under 7% of the 1,210 records, well below the 58.8% and 55.2% held by the core C21D and B24C classes. That gap suggests thinner claim density around vibration-damping component treatment, non-ferrous alloy peening protocols, and general coverage-optimisation processes outside the dominant heat-treatment and abrasive-blasting core. A freedom-to-operate check in those narrower subclasses is a reasonable starting point before assuming the space is open.
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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.