The dataset's leading assignee holds 1,602 of the 4,500 records in scope, well ahead of the rest of the ranked leaders — fifth place holds 183 and tenth place holds 44. Together the top five assignees account for 68.3% of all records, so the field is concentrated among a small number of aerospace engine manufacturers and their composites divisions rather than spread evenly. Anyone assessing freedom to operate should treat this small group as the primary reference set rather than sampling the wider ranking.

Yes, based on the last full years of data: filings rose from 198 in 2021 to 275 in 2024, a 39% increase over that span. The peak year on record so far is 2018, at 357 filings, but growth resumed and continued through 2024. Figures for 2025 and 2026 appear lower only because patent publication typically lags actual filing by around 18 months, not because activity has slowed.

Coating and surface deposition claims for CMC hot-section parts fall mainly under C23C, which appears on 12.0% of the 4,500 records in this dataset, often alongside C04B ceramics claims (55.2% of records) and B32B layered-product claims (13.3%). This lower share relative to the core ceramics and turbine classes suggests environmental barrier coating durability, including resistance to water vapour recession, is a comparatively less crowded claim area than fibre or matrix processing itself.

US20220055954A1, filed by Central South University, claims an automated process that combines chemical vapour infiltration for the fibre interface layer with reactive melt infiltration for final densification, applied to a specific winding and net-shape preforming sequence for a flame tube. It does not claim CMC materials or flame tube parts generally; it claims a particular automated process sequence. Processes that use a different densification order, a different preform-forming method, or that omit the automated winding step are outside the specific process claims described here, though a full claim-by-claim comparison against the granted claims is needed before relying on that distinction.

Relative to the dominant C04B and F01D classes, combustion-chamber-specific applications (F23R, 6.5% of records), gas-turbine plant integration (F02C, 6.2%) and clay/cement-based shaping routes (B28B, 4.6%) carry noticeably lower record density. Compliant attachment mechanisms and water-vapour-recession-resistant coating top coats also show up as narrower, less-crowded claim areas within the broader coating and attachment space. These lower-density branches are worth checking first for a first-claim opportunity, since the core fibre, matrix and turbine-integration claims are already occupied by a handful of large portfolios.