The dataset ranks 100 assignees by record count, with the leading assignee holding 204 records against 2,522 total in scope. The top five assignees combined hold 589 records, 23.4% of the field, and the top ten hold 860 records, 34.1%. That leaves the majority of filings distributed across the remaining ranked companies and smaller, unranked entrants, so no single assignee controls the field outright.

Complete-year data shows filings peaked at 227 in 2022 and eased to 179 by 2024, an 11% decline from 2021’s 200 filings over that span. That is a plateau after a peak rather than a sustained collapse. Figures for 2025 and 2026 are still incomplete because publication typically lags filing by around eighteen months, so recent-year totals should not be read as evidence of continued decline until later data fills in.

Almost all records, 96.7% of the 2,522 in scope, sit in H01M, the core battery and cell classification. Smaller but consistent overlaps appear with H01G capacitors (4.8%), C01B non-metallic inorganic compounds (4.2%), C01G metal compounds (3.6%), H02J power supply systems (2.2%), H01B conductors (1.8%), C04B ceramics (1.7%) and B82Y nanotechnology (1.5%). Because a single record can carry multiple IPC classes, these shares add up to more than 100%.