One assignee leads the ranked field with 76 of the 222 records in scope, a wide margin ahead of fifth place at 5 records and tenth place at 4. The remaining 74 ranked assignees form a long tail of small-volume filers, many with only one or two records, typically tied to a specific formulation or application rather than a broad platform. This concentration means competitive freedom-to-operate analysis should start with the leader’s claims before looking at the tail.

Filing activity peaked at 13 records in 2017 and has since settled into a lower, flat pattern, with 3 filings in 2021 and 3 in 2024 — a 0% change over that span. This reads as a mature, steady-state technology area rather than one in active expansion or decline. Figures for 2025 and 2026 are still incomplete because publication typically lags filing by around 18 months, so recent years should not be read as a drop-off.

C02F, covering water and wastewater treatment, appears on 73.0% of the 222 records and is by far the dominant class. But a meaningful share also touches fertiliser-related classes — C05B (phosphate fertilisers) at 15.3% and C05F (organic and waste-derived fertilisers) at 14.4% — reflecting overlap between metal-precipitation chemistry and byproduct or nutrient-recovery streams. Separation processes (B01D, 14.9%) and various inorganic compound classes (C01B, C01D, C01G) also recur, indicating the chemistry crosses several adjacent industrial uses.