The dataset ranks 100 companies by record count, led by a single assignee with 17 records, with fifth place at 11 and tenth place at 6. The top 5 assignees combined account for 19.6% of all 311 records in scope, and the top 10 for 30.9%, which means the majority of filings sit outside the most active names. This is a field with recognisable leaders rather than one dominated by a single company, so a competitive review should look past the top few names to the wider ranked list.

Filing rose from 16 records in 2021 to 19 in 2024, a 19% increase over that three-year span, and 2025 recorded the highest annual count in the dataset so far. The apparent low count in 2026 is an artifact of publication lag, which typically runs about 18 months behind actual filing, not a real drop in activity. Based on the complete years available, the trend through 2024 is one of steady growth rather than slowdown.

The two most-claimed IPC subclasses are H10N (other electric solid-state devices) at 79.1% of the 311 records and H01L (semiconductor devices) at 61.7%, meaning most filings frame their claims at the device or semiconductor-structure level. Materials-focused classes such as C01B (non-metallic elements and inorganic compounds, 19.6%), C22C (alloys, 12.9%) and C04B (ceramics, 9.6%) are present but claimed far less densely. Because a single record can carry multiple IPC codes, these shares add up to more than 100% and should be read against the 311-record total, not against each other.

The thinnest-claimed IPC classes relative to the core device classes are B82Y (nanotechnology applications, 7.1%), C30B (crystal growth, 6.4%) and C23C (coating and surface deposition, 5.1%). These correspond to mechanism-level work — phonon-scattering nanostructuring, crystal-growth-based control of grain boundaries, and coating-based thermoelectric interfaces — that is documented in far fewer filings than device-integration claims. A first claim in these branches would likely need to specify a particular processing route or material system to avoid overlapping with the small number of existing filings there.

US20130186449A1, filed by Micross Advanced Interconnect Technology, LLC, claims a thermoelectric material and converter where a rare earth component is incorporated into a semiconductor base to raise the composite's figure of merit above that of the semiconductor alone, with the rare earth addition usable in either the p-type or n-type leg of the converter. It does not block thermoelectric work generally; it is specific to rare-earth-doped semiconductor composites used this way. Filings using different dopant chemistries, different structural mechanisms such as nanostructuring or band convergence, or non-rare-earth approaches to raising zT would sit outside its claim scope, though a detailed claim chart is needed before relying on that reading.