One assignee leads the ranked field with 592 records, a clear margin over fifth place at 153 and tenth place at 116. That gap indicates a genuine leader rather than a crowded top tier, though the top ten assignees together still only account for 32.3% of the 7,486 records in scope, so most of the field sits outside their portfolios. Anyone doing freedom-to-operate work should check the leader’s claims first, then work down the ranking rather than assuming coverage is evenly spread.

Filings peaked in 2017 at 300 and had eased to 212 by 2024, a -12% change across that three-year span. That reads as a maturing claim map rather than an abandoned field — the core compliance-curve and burst-pressure mechanics are well covered, which naturally reduces the rate of new filing in that specific territory. Figures for 2025 and 2026 are still incomplete because publication typically lags filing by around 18 months, so the most recent years should not be read as a further decline.

The two dominant IPC subclasses are A61M (devices for introducing media into the body) at 53.9% of the 7,486 records and A61F (implants and prostheses) at 50.1%. A61B (diagnosis and surgery) and A61L (sterilising and disinfecting) form a second tier, while A61K, B29C, A61N and A61P are present but comparatively thin. Because a single record can carry multiple IPC classes, these shares add up to more than 100% and should not be summed.