This dataset covers 2,239 patent families published between 2015 and mid-2026 that claim temperature uniformity, frost formation control, vacuum insulation panels, variable-speed compressors or humidity control in refrigerators and food preservation compartments. Filing peaked in 2020 at 148 families and has declined since, reaching single digits in the most recent partial year. Because publication lags filing by roughly 18 months, the latest year's count will revise upward as more records publish.

Filing is concentrated among a small set of major appliance manufacturers, with Haier's group entities showing the strongest internal co-assignment link at 94 shared families. Samsung, LG, Whirlpool and Toshiba also appear prominently in the ranking, though several of these leaders show sharp year-on-year declines — some down more than 80% — in the most recent year. That pullback is consistent with a filing plateau across the leadership tier rather than any single company exiting the field.

The core F25D subclass, covering refrigerators and cooling generally, appears in 2,171 of the 2,239 records, making it the dominant claim surface. Meaningful secondary density sits in F25B (refrigeration and heat pumps), F16L (pipe fittings) and F25C (ice making), meaning a search limited to the core subclass will miss adjacent blocking claims. Smaller but distinct pockets exist in laminate materials, furniture hardware and food composition classes.

Comparatively thin filing density shows up in areas like adsorbent-integrated vacuum panel seals, humidity-zoned crisper compartment design, and door-hinge sensor integration, which sit at the intersection of the dominant F25D subclass and smaller adjacent classes like E05D and B32B. These are not unclaimed spaces, but they carry far fewer records than the core compressor and insulation claims, which suggests room for a narrowly drafted first claim rather than a broad blocking position.

US10337787B2, assigned to Samsung Electronics and published 2019-07-02, claims a refrigerator vacuum insulation panel built from a core material, a covering material forming an accommodation space, and a first adsorbent activated above room temperature to remove gases and water from that space. The claim ties panel construction directly to an in-situ adsorbent step, which narrows the room for a competing vacuum-insulated cabinet that uses a similar adsorbent-activation mechanism. It does not block vacuum insulation generally — only designs that combine the same core, covering and adsorbent-activation elements in this specific arrangement.