Sulfur Removal and Recovery Patents: Who Leads, White Space 2026
Sulfur Removal and Recovery Patents: Mapping the Claus Process Field
Filing peaked in 2020 at 107 records and has fallen sharply since — 2021's 42 filings dropped to 17 by 2024, a 60% decline over that three-year span. Filings rose to a peak of 107 in 2020, then declined — 2021's 42 fell to 17 by 2024, a 60% drop over that three-year window. 2025 and 2026 figures are still incomplete due to publication lag and should not be read as a continuation of the decline.
- 1SAUDI ARABIAN OIL CO9.4%
- 2HALDOR TOPSOE AS6.8%
- 3SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ BV5.1%
- 4FLUOR TECH CORP4.4%
- 5AMOCO CORP4.4%
See the full sulfur removal and recovery 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 on sulfur recovery patents
Who holds the most patents in sulfur recovery and Claus process technology?
One assignee leads the field with 138 records, well ahead of fifth place at 64 and tenth place at 30, so the field has a clear leader rather than an even spread. The top 5 assignees together hold 30.1% of all 1,463 records in scope, and the top 10 reach 44.4%. Below that concentration sits a long tail of companies with only a handful of filings each, which is typical of a field anchored by refining majors and process licensors rather than a fragmented field of specialist startups.
Is patent filing in sulfur recovery technology growing or shrinking?
Filing peaked at 107 records in 2020 and declined afterward, with 2021’s 42 filings falling to 17 by 2024 — a 60% drop over that three-year span. That said, patent publication typically lags filing by around 18 months, so the 2025 and 2026 figures in any dataset are still incomplete and should not be read as continuing the decline. Treat 2024 as the most recent year with a reasonably complete picture.
What patent classes cover Claus process and sulfur recovery unit technology?
The dominant classes are C01B, covering non-metallic elements and inorganic compounds, which appears on 77.0% of the 1,463 records in scope, and B01D, covering separation processes, on 60.1%. B01J, chemical and physical processes including catalysis, appears on 27.3% of records. Downstream-facing classes such as fuel gas purification, fuel treatment, combustion apparatus, oil refining and gasification each sit under 4% of records, indicating those areas carry far fewer competing claims.
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 Sulfur Removal and Recovery 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.