Filing in this corpus is dominated by Chinese universities and research institutes rather than a single commercial leader, with the momentum table showing small, single-digit annual counts for the most active filers. South China University of Technology shows the strongest recent-year growth, at +100% year over year, and anchors the strongest co-assignee pairing in the dataset with an affiliated spin-out. No single entity holds a commanding share of the 1,790 tracked families, which points to a fragmented, still-forming ownership structure rather than a settled market with clear incumbents.

Annual filings rose from 58 in 2017 to a peak of 301 in 2025, roughly doubling the 2022 midpoint of 157, so the underlying trend through 2025 is upward. The apparent drop to 55 filings in 2026 is misleading: patent publication typically lags filing by around 18 months, so the most recent one to two years in any filing trend are always undercounted. Read the 2025 figure as the most reliable recent signal, and expect 2026's true total to rise as more records publish.

G06F (electric digital data processing) appears on 1,758 of the 1,790 tracked records, making it close to a universal classification in this corpus, followed by A61B (diagnosis and surgery) at 728 and G06N (AI-based computing) at 363. A61F (implants and prostheses) appears on only 60 records. This split means the bulk of active claim-drafting in this field concerns signal processing, decoding algorithms, and control logic rather than implantable hardware design, which has direct implications for where prior-art searches should focus.

China's patent office received 1,125 of the tracked filings, more than six times the US total of 185, with India (150), South Korea (109), the PCT route (84), and the EPO (79) trailing well behind. A filing or clearance strategy built only around the US and Europe will miss the majority of the documented activity in this field. Organisations doing freedom-to-operate work in this space should treat Chinese-language prior art as a primary, not secondary, search target.

US20250216942A1, filed by KINGFAR INTERNATIONAL INC. and published 2025-07-03, claims a method for controlling a brain-computer interface device that extracts a multi-modal feature from EEG data plus on-screen image data, maps it to a fuzzy set, and derives a control instruction from that set. It is representative of the corpus's dominant claim style: signal-plus-context fusion feeding a decision layer, rather than a change to implant or electrode hardware. Anyone drafting in adjacent multi-modal decoding space should review this filing's specific fuzzy-set mapping step, since that is the narrower, more design-around-able element of the claim chain.

Filing density is uneven rather than uniformly saturated: G06F-coded decoding-software claims are dense, while A61F-coded implant-hardware claims and A61N-coded electrotherapy-integrated control claims are comparatively sparse. Co-assignee collaboration is also thin, with only 10 identified pairs across 1,790 families, suggesting most organisations are prosecuting independently rather than building joint patent estates. Sub-areas such as multi-modal EEG-plus-image fusion pipelines and fuzzy-set-based instruction derivation show lighter claim density than the core decoding cluster and are worth a closer freedom-to-operate look before committing to a filing strategy there.