The leading assignee holds 592 records in this dataset, a steep drop from fifth place at 127 and tenth place at 85. Even so, the top 5 assignees combined account for only 15.8% of the 9,357 records in scope, and the top 10 for 21.6%, so no single company controls the field. The ranked leaders mix consumer electronics, industrial controls, connected-health device makers and telecom-standards holders, reflecting how broadly moisture sensing has been embedded into other product categories.

Filing volume rose from 473 records in 2017 to a peak of 687 in 2022, then eased to 530 by 2024 — a -12% change from 2021's 600. That reads as a moderation off a peak rather than a collapse. Figures for 2025 and 2026 are still incomplete because publication lags filing by roughly 18 months, so any apparent recent drop should not be treated as a real slowdown until later data fills in.

G01N, material analysis and testing, is the single largest IPC class, touching 20.1% of the 9,357 records in scope. H04W wireless networks (9.1%) and G06F digital data processing (8.4%) follow, well ahead of air conditioning, diagnostic and control-systems classes. Because a single record can carry multiple IPC codes, these shares add up to more than 100%, and they show that moisture-sensing claims increasingly overlap with connectivity and data-processing claims rather than sitting in a standalone sensor category.

US6126311A covers a dew point sensor architecture built around a micro-cantilever beam whose resonance shifts as dew mass forms on it, combined with a cooling device, a temperature sensor and a control circuit that coordinates all three. Anyone building a MEMS-based dew point sensor that determines dew point from a resonance shift driven by condensation mass should review this claim structure closely. Alternative approaches — capacitive polymer sensing, optical condensation detection, or bulk-property measurement that does not rely on a resonating cantilever — sit outside this specific mechanism.

Co-assignee filing is rare, with only 10 identified pairs across the entire corpus, suggesting most innovation here happens inside single organisations rather than joint ventures. Specific sub-areas — condensation recovery in sealed enclosures, salt-solution calibration drift correction, and sensor poisoning resistance for capacitive polymer elements — sit below the dominant G01N and H04W classes and away from the leading assignee's core filings. These are reasonable places to start a freedom-to-operate check before drafting claims in the more crowded material-analysis space.