Patent ownership is led by a small group of established chemical and materials companies, with the top-ranked assignee holding 3,990 records out of 41,450 in this dataset. The next four assignees combined bring the top-five share to 17.7% of all records, and the top ten to 25.2%. That leaves roughly three-quarters of filings spread across a long tail of other companies, so leadership is real but far from exclusive — new entrants still have room to build a defensible position outside the densest claim clusters.

Filing activity peaked in 2019 at 1,072 records and has declined since, with a documented drop from 877 filings in 2021 to 389 in 2024 — a 56% fall over that three-year span, the most recent period with complete publication data. Momentum figures for individual leading assignees also show steep year-over-year declines in the latest tracked year. Figures for 2025 and 2026 are still incomplete because publication typically lags filing by around 18 months, so the true recent trend will only be clear once those years finish filling in.

The densest IPC classification is C08L, covering polymer compositions generally, at 13.0% of the 41,450 records in scope. B32B (layered products and laminates) and C08K (additives) follow at 8.6% and 8.2% respectively, with shaping-related classes B29C and C08J each near 7.2%. Because a single record can carry multiple IPC classes, these shares add up to more than 100% of the record total — they describe overlapping technical facets of the same filings, not mutually exclusive categories.