OCD Scatterometry Patents: Who Leads, Where the Gaps Are 2026
Optical Critical Dimension Scatterometry Patents: Mapping the Field Through 2026
89.7% concentration. The top five assignees hold 1,840 of 2,052 records in scope — a leaderboard with almost no long tail beyond the leader. Annual filings climbed from 139 in 2017 to a peak of 161 in 2018, then declined through the confirmed window to 76 in 2024 (down 41% from 128 in 2021). Counts for 2025 and 2026 are not yet complete because of publication lag and should not be read as a continued fall.
- 1ASML NETHERLANDS BV761
- 2KLA CORP723
- 3TOKYO ELECTRON LTD168
- 4NOVA MEASURING INSTR LTD138
- 5ONTO INNOVATION INC50
See the full optical critical dimension scatterometry 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 this landscape
Who holds the most patents in optical critical dimension scatterometry?
One assignee holds 761 of the 2,052 records in scope, well ahead of the rest of the ranked leaders — fifth place holds only 50 records. This is a field where a single company’s portfolio dominates rather than one split among several comparably sized players. Anyone assessing freedom to operate here should expect the bulk of relevant prior art to trace back to that one leader, with the remaining top-five assignees together making up most of what is left.
Is the OCD scatterometry patent field still growing?
Filing activity peaked in 2018 at 161 records and has since eased, with a confirmed drop from 128 filings in 2021 to 76 in 2024 — a 41% decline over that span. However, publication lag of roughly 18 months means 2025 and 2026 counts are still incomplete and should not be read as the field ending. The honest read is a mature field cooling from a high point, not one in active collapse.
What technology areas overlap most with OCD scatterometry patents?
Photolithography and photomechanics (IPC class G03F) appears in 48.2% of the 2,052 records, and material analysis and testing (G01N) in 42.2%, making these the two dominant overlapping fields. Measuring length and dimensions (G01B) and semiconductor devices (H01L) each cover roughly a quarter to just under a third of records. Because a single record can carry multiple IPC classes, these shares add up to more than 100% and should be read as overlap density, not as mutually exclusive segments.
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 Optical Critical Dimension Scatterometry 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.