The dataset ranks 100 assignees by record count, with the leading assignee holding 50 records against 27 at fifth place and 12 at tenth — a steep drop rather than a gradual taper. The top 5 assignees combined hold 200 of the 482 records in scope, or 41.5%, and the top 10 combined hold 60.4%. That concentration means a small number of filers control most of the documented claim space around core force and haptic sensing architectures, so any freedom-to-operate check should start with those leading positions rather than the long tail.

Filings peaked at 62 in 2018, then declined before rebounding: 9 filings in 2021 climbed to 17 in 2024, an 89% increase over that three-year span. Because publication lags filing by roughly eighteen months, the 2025 and 2026 figures in any chart are still incomplete and should not be read as a slowdown. Taken together, the pattern looks like renewed engineering interest after a mid-decade lull rather than a maturing or declining field.

EP3148472A1, filed by The Johns Hopkins University and published in 2017, covers a multi-force sensing instrument with a strain sensor at one position on a tool shaft and a second strain or torque-force sensor further toward the proximal end, combined by a signal processor to resolve the magnitude and position of a lateral force component. The claim structure is built around separating axial and lateral force measurement along a single shaft using two spaced sensing points rather than one. Anyone designing a tip-force or grip-force sensing instrument for a robotic surgical tool should check this architecture specifically, since it predates much of the later filing activity in the space.

Relative to the dominant A61B (39.8% of 482 records) and B25J (21.2%) classes, sub-areas like scanning-probe and nanometric measuring overlap (G01Q, 5.8%) and vehicle-adjacent force sensing (B60R, 6.4%) carry noticeably thinner claim density. Within the search terms themselves, sensor sterilizability and grip-force estimation approaches that avoid dedicated strain gauges appear less frequently in the most-cited records than tip-force sensing does. These are reasonable areas to search more deeply before filing, though a low class share is a signal to investigate, not proof that the space is genuinely open.

With the top 5 assignees at 41.5% of 482 records and the top 10 at 60.4%, this field sits toward the concentrated end: a majority of documented activity is controlled by ten organisations out of the 100 that appear in the ranking. That said, the drop from the leader's 50 records to 12 at tenth place shows the concentration is front-loaded around one or two dominant filers rather than evenly spread across the top ten. New entrants should expect meaningful prior art from the leading assignees on any core sensing or control claim, with more room to differentiate further down the ranking.