TMCP claims typically combine an alloy composition window with a specific rolling and cooling schedule — finish rolling temperature, coiling temperature and accelerated cooling rate are the recurring variables. In this dataset, 83.8% of the 2,174 records in scope touch alloy composition (C22C) and 78.8% touch heat treatment (C21D), often in the same claim set, which shows applicants usually protect the metallurgy and the process path together rather than either alone. Rolling equipment claims are comparatively less common at 18.1%, so a novel mill-side control method may face a less crowded field than a novel steel chemistry.

Filing is concentrated: the top 5 assignees together hold 53.0% of the 2,174 records in scope, and the leading assignee alone holds 313 records against 41 at tenth place. This is a field dominated by integrated steelmakers with in-house metallurgy research rather than a fragmented mix of small filers. Anyone doing a freedom-to-operate check should prioritise searching the concentrated top of the ranked assignee list before assuming the field is open.

Filings peaked at 118 in 2022 and the documented three-year window shows a 32% decline from 74 in 2021 to 50 in 2024 — a genuine slowdown in the mature core of the technology. However, counts for 2025 and 2026 are still incomplete because publication typically lags actual filing by around 18 months, so the very latest years should not be read as continuing that decline. The honest read is: activity cooled through 2024, and the trend beyond that is not yet determinable from published data.