Ladle Furnace Refining Patents: Top Filers & Filing Trends 2026
Ladle Furnace Refining Patents: Who Leads and Where Filing Is Heading
34.1% concentration at the top. The five leading assignees hold 117 of 343 records in scope, a level of concentration that narrows the open claim space for slag reduction and alloy recovery chemistry. Filings rose from 3 records in 2017 to a peak of 42 in 2022, then declined to 9 by 2024 — a -57% move from the 21 recorded in 2021. 2025 and 2026 figures are still incomplete due to publication lag and should not be read as a continued fall.
- 1JFE STEEL CORP42
- 2NIPPON STEEL CORPORATION22
- 3SANYO SPECIAL STEEL CO LTD19
- 4INST OF RES OF IRON & STEEL JIANGSU PROVINCE17
- 5JIANGSU SHAGANG GROUP CO LTD17
See the full ladle furnace refining analysis in Eureka
- The complete ranking, not just the top five
- Every IPC branch with its share of the corpus
- The most-cited records, and where claim space is still thin
Common questions about ladle furnace refining patents
Who holds the most patents in ladle furnace refining?
The leading assignee in this dataset holds 42 of the 343 records in scope, well ahead of the fifth-ranked filer at 17 and the tenth at 12. The top five assignees combined account for 34.1% of all records, and the top ten reach 53.6%. That leaves a long tail of the remaining ranked companies filing only a handful of records each, so ownership is concentrated at the top but far from closed.
Is ladle furnace refining patent filing growing or slowing?
Filing peaked at 42 records in 2022 after rising from just 3 in 2017, then declined to 9 records by 2024 — a -57% move from the 21 filed in 2021. Because patent publication typically lags actual filing by around 18 months, the 2025 and 2026 figures in any chart are still incomplete and should not be read as proof the technology is losing momentum. 2024 is the most recent year that can be treated as a reasonably complete data point.
What technology areas dominate ladle furnace refining patents?
Steelmaking process claims under IPC class C21C appear in 69.4% of the 343 records, making it by far the largest category. Alloy composition (C22C) follows at 24.5% and metal casting (B22D) at 14.3%, while refractory materials (C04B) and furnace hardware (F27D) each sit at only 8.5%. Because a single patent can carry multiple IPC codes, these shares add up to well over 100% of the record total, which is expected.
Disclaimer. This analysis is based on Patsnap Eureka data drawn from a limited snapshot of global patent records and is provided for general information and reference only. Patent data carries inherent limitations — recent filings are under-counted because of publication lag, counts may be on a record or family basis, classification and applicant-name data may contain errors or duplicates, and the underlying search query defines the scope shown — so the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing here is an exhaustive prior-art, novelty, freedom-to-operate or validity search, nor does it constitute legal, financial or professional advice, and it should not be relied upon as such. Verify independently and review with qualified patent and legal professionals before acting on it.
Method: Filing trend and technology composition. Derived from a Patsnap search on Ladle Furnace Refining covering 2015–2026, data cut-off 2026-07-31. Counts reflect published records only and shift as new filings publish. Every share divides by all records in scope. Data: Patsnap Eureka. See the full landscape report.