One assignee leads clearly with 271 of the 838 records in scope, well ahead of the fifth-ranked company at 25 and the tenth-ranked at 13. The top five assignees combined hold 50.4% of all records, so ownership is concentrated but not limited to a single company. Behind the ranked leaders sits a long tail of smaller filers, many with only one or two records, which is typical for a materials technology with both large manufacturers and academic or niche filers active in it.

Filing rose from 27 records in 2017 to a peak of 67 in 2021, then fell to 28 by 2024, a -58% change over that three-year span. That drop looks like a cooling-off after an initial wave of claims rather than the field disappearing, since the underlying motor-efficiency drivers behind soft magnetic composite research have not gone away. Figures for 2025 and 2026 are still incomplete because publication typically lags actual filing by around 18 months, so those two years should not be read as confirming a continued decline.

The two dominant classes are H01F, covering magnets, inductors and transformers, which appears on 65.4% of the 838 records, and B22F, covering powder metallurgy, on 41.9%. H02K, the electric motors and generators class, reaches 26.7%, reflecting how much of this work is claimed with an end application in mind. Coating-specific class C23C and casting class B22D sit much lower, at 4.7% and 3.9% respectively, which is one indicator of where claim space is less crowded.