Air Purification & Indoor Air Quality Patent Landscape
The air purification and indoor air quality field is moderately concentrated, with LG Electronics holding a clear lead and the top five filers collectively dominating activity among the largest hundred applicants. Annual filing volume surged to a 2021 peak and has since eased, signalling a maturing competitive environment rather than continued expansion.
LG Electronics leads a Korean- and Chinese-dominated field
LG Electronics is the clear portfolio leader, followed by Coway, Samsung Electronics, Gree Electric Appliance, and Donaldson — a mix of Korean consumer-electronics giants, Chinese appliance manufacturers, and one dedicated industrial filtration specialist.
The top five filers account for 37% of the combined output of the hundred largest filers, indicating meaningful concentration at the top but a long tail of active second- and third-tier players that keeps the competitive landscape contestable.
| # | Applicant | Patent families | Share |
|---|---|---|---|
| 1 | LG Electronics Inc | 608 | |
| 2 | Coway Co Ltd | 337 | |
| 3 | Samsung Electronics Co Ltd | 296 | |
| 4 | Gree Electric Appliance Inc of Zhuhai | 288 | |
| 5 | Donaldson Co Inc | 232 | |
| 6 | Sharp Corporation | 123 | |
| 7 | Blueair | 115 | |
| 8 | Panasonic Holdings Corporation | 113 | |
| 9 | Qingdao Haier Air Conditioner General Corp Ltd | 105 | |
| 10 | Haier Smart Home Co Ltd | 95 |
| # | Applicant | Patent families | Share |
|---|---|---|---|
| 11 | 3M Innovative Properties Co | 93 | |
| 12 | Mann+Hummel GmbH | 87 | |
| 13 | Koninklijke Philips NV | 85 | |
| 14 | Carrier Corporation | 77 | |
| 15 | Midea Group Co Ltd | 76 | |
| 16 | Mitsubishi Electric Corporation | 72 | |
| 17 | Seoul Viosys Co Ltd | 61 | |
| 18 | Daikin Industries Ltd | 59 | |
| 19 | GD Midea Air Conditioning Equipment Co Ltd | 58 | |
| 20 | Chung-Ang University Industry-Academic Cooperation Foundation | 50 |
LG’s scale advantage and its simultaneous strength in both filtration (B01D) and ventilation-system (F24F) subclasses suggests a platform approach that is difficult to replicate quickly; challengers such as Samsung and Gree are narrowing the gap in specific subclasses but have not yet matched LG’s breadth.
Filings from approximately 2024 onward are subject to publication lag and will be revised upward as patent offices complete examination; treat recent-year counts as provisional. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
A 2021 peak followed by easing volume; ventilation and filtration dominate the technology mix
Two charts capture the field’s temporal and structural shape: annual filing volume from 2017 to 2026, and the distribution of activity across IPC technology classes.
Annual filing trend
Filings roughly doubled between 2017 and 2019, then surged sharply through 2020–2021 — likely amplified by pandemic-era indoor-air concerns — before retreating toward pre-surge levels by 2023–2024. The 2025–2026 bars are heavily undercounted due to publication lag and should not be read as a continuation of the downward trend.
↗ Hover for values · click a bar to ask EurekaTechnology composition
Air conditioning and ventilation (F24F) and separation/filtration processes (B01D) are the two dominant classes and together account for the large majority of activity. Sterilisation and disinfection (A61L) is a meaningful but clearly smaller third branch, while vehicle HVAC (B60H), electrostatic separation (B03C), catalysis (B01J), and lighting components (F21V) each represent smaller but potentially distinct technology niches.
↗ Hover for values · click a bar to ask EurekaHighly cited patent families surfaced by the query
Citation-heavy patent families returned by the query. Use this section as citation context, not as a curated list of the most topic-specific patents.
Air cleaning member, air cleaning unit and air con…
An air purification member is provided that can reduce the generation of unpleasant odor or the occurrence of air contamination without necessitating frequent cleaning or replacement. The air purification member can be part of an air purification unit or an air conditioning apparatus. A first photocatalytic filter of an air purifier is a filter for… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Air filtration arrangements having fluted media co… | 907 |
| 2 | Air filtration system with filter efficiency manag… | 392 |
| 3 | Air purification system | 344 |
| 4 | Air purifier with intelligent sensors and airflow | 311 |
| 5 | Air purifier | 292 |
| 6 | 空气净化器 | 288 |
| 7 | 空气净化结构和空气净化系统 | 280 |
| 8 | Air purifier based on filter Anti-counterfeiting i… | 267 |
Ranked by total forward citations. Citation counts favour older and broadly cited patent families, and broad or adjacent patents may appear when they match the search scope. Treat this section as citation context, not as a curated list of the most topic-specific patents. Some patent titles may be shown in their original, non-English language where an accurate translation could not be guaranteed.
What the competitive structure means for R&D strategy
Four structural observations — maturity, concentration, collaboration, and geography — frame the strategic context for any new entrant or incumbent deciding where to allocate resources.
Field has passed its peak and is consolidating
Annual filing volume peaked in 2021 and has eased since, placing the field in a post-peak phase. The multi-year corpus of 15,295 patent families confirms substantial prior-art density; new entrants face a high bar for differentiation and freedom-to-operate. Investment focus is shifting from volume to quality and specificity.
Post-peakModerate top-end concentration with a competitive long tail
The top five filers hold 37% of the hundred largest filers’ combined output, a level that reflects genuine scale advantages but not monopolistic control. The ranking beyond position five is fragmented across Korean, Chinese, Japanese, American, and European players, preserving room for specialised challengers. A clear two-tier gap exists between the top five and the next fifteen.
Two-tier marketHaier’s internal ecosystem and LG’s university ties are the most active co-filing networks
The most frequent co-filing pairs are within the Haier group: Qingdao Haier Air Conditioner General Corp and Haier Smart Home filed jointly 62 times, and Qingdao Haier Air Conditioner and Qingdao Haier Air Conditioning Electronics co-filed 44 times. LG Electronics is the leading inter-institutional collaborator, co-filing 33 times with Chung-Ang University and twice with UNIST (Ulsan National Institute of Science and Technology). Donaldson and Ahlstrom co-filed 5 times, representing the most active cross-company pairing outside China and Korea.
Ecosystem co-filingChina is the dominant filing jurisdiction; US and Korea are distant second and third
China accounts for the largest share of patent records by a wide margin, reflecting both the scale of the Chinese appliance market and strategic defensive filing by Chinese applicants. The United States and South Korea are the next most active jurisdictions, followed by Europe (EPO) and WIPO. This concentration means that freedom-to-operate analysis must prioritise China, even for companies whose primary markets are elsewhere.
China-centricGo beyond the landscape: Eureka’s TRIZ Solution agent breaks down an R&D problem and returns patented concept solutions, each with a technical approach and cited patent & literature evidence.
| Applicant | Collaborator | Co-filings |
|---|---|---|
| Qingdao Haier Air Conditioner General Corp Ltd | Haier Smart Home Co Ltd | 62 |
| Qingdao Haier Air Conditioner General Corp Ltd | Qingdao Haier Air Conditioning Electronics Co Ltd | 44 |
| LG Electronics Inc | Chung-Ang University Industry-Academic Cooperation Foundation | 33 |
| LG Electronics Inc | CHUNGANG UNIV IND ACADEMIC COOP | 11 |
| Qingdao Haier Air Conditioner General Corp Ltd | Qingdao Haier Smart Technology R&D Co Ltd | 8 |
| Donaldson Co Inc | Ahlstrom Corporation | 5 |
| Sharp Corporation | Suminoe Textile Co Ltd | 5 |
| Sharp Corporation | Osada Minoru | 4 |
| LG Electronics Inc | Ulsan National Institute of Science and Technology (UNIST) | 2 |
| LG Electronics Inc | CHUNGANG UNIV IND ACADEMIC CORPORATIONFOUNDATION | 2 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
LG Electronics and Coway lead; Samsung accelerating while LG and Blueair pull back
The top two players differ meaningfully in portfolio breadth and recent trajectory, and the challenger tier shows divergent momentum that is reshaping relative positions.
LG Electronics
LG Electronics holds 608 patent families — the largest portfolio in the field — with primary emphasis on filtration separation (B01D 46), air purification systems (F24F 8), and structural HVAC components (F24F 13). This breadth reflects a platform strategy spanning both the consumer purifier and broader HVAC segments. Recent filing momentum has contracted sharply (▼ –71% vs. the prior three-year window), suggesting the company is consolidating rather than expanding its position.
families: 608Samsung Electronics
Samsung Electronics holds 296 patent families and shows the strongest recent momentum among profiled players (▲ +132% vs. the prior three-year window), suggesting a deliberate acceleration in indoor air quality investment. Its technology focus mirrors LG’s — filtration (B01D 46), air purification (F24F 8), and structural components (F24F 13) — but at roughly half the accumulated scale, leaving a meaningful gap to close. The acceleration is notable but should be read in the context of a lower prior base.
families: 296| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| LG Electronics Inc | 51 | ▼ -71% |
| Gree Electric Appliance Inc of Zhuhai | 101 | ▼ -7% |
| Samsung Electronics Co Ltd | 65 | ▲ +132% |
| Coway Co Ltd | 49 | ▼ -22% |
| Donaldson Co Inc | 23 | ▬ 0% |
| Koninklijke Philips NV | 1 | ▲ new entrant |
| Blueair | 14 | ▼ -81% |
| Sharp Corporation | 7 | ▼ -56% |
Under-served branches adjacent to the dominant filtration and ventilation core
Several IPC classes appear at materially lower activity levels relative to F24F and B01D; these represent observations of relative sparsity rather than confirmed commercial gaps, but some carry plausible technical and market relevance worth monitoring.
B03C · Electrostatic & magnetic separation
With 488 patent records against the dominant classes’ tens of thousands, electrostatic precipitation as a primary purification mechanism remains sparsely covered relative to its technical potential. Electrostatic collectors offer filter-free operation — a meaningful differentiator for maintenance-sensitive commercial and healthcare environments. Entry requires expertise in high-voltage miniaturisation and ozone-emission management, which narrows the realistic applicant pool but also limits crowding.
Search this in Eureka →B01J · Chemical processes & catalysis
Catalytic degradation of VOCs and biological contaminants appears in only 308 patent records, a small share relative to the filter-centric mainstream. Photocatalytic and thermocatalytic approaches — particularly at ambient temperatures — are technically attractive for removing gaseous pollutants that HEPA filters cannot capture. The sparse coverage may reflect both technical difficulty and the limited number of companies with catalyst materials expertise, suggesting a potential entry path for materials science and chemistry-oriented players.
Search this in Eureka →How leading applicants differ across technology routes
Route coverage across the main technology branches in the current evidence set.
| Player | B01D 46 · Separation processes (filtration etc.) | F24F 8 · Air conditioning & ventilation | F24F 13 · Air conditioning & ventilation | B01D 53 · Separation processes (filtration etc.) | F24F 11 · Air conditioning & ventilation |
|---|---|---|---|---|---|
| LG Electronics Inc | Strong · 287 | Strong · 261 | Strong · 183 | Absent | Moderate · 75 |
| Gree Electric Appliance Inc of Zhuhai | Moderate · 81 | Strong · 190 | Strong · 140 | Emerging · 15 | Strong · 119 |
| Samsung Electronics Co Ltd | Strong · 176 | Strong · 125 | Moderate · 84 | Emerging · 28 | Moderate · 57 |
| Coway Co Ltd | Strong · 196 | Strong · 108 | Moderate · 91 | Absent | Moderate · 42 |
| Koninklijke Philips NV | Moderate · 47 | Strong · 95 | Absent | Emerging · 18 | Strong · 83 |
| Donaldson Co Inc | Strong · 172 | Absent | Absent | Absent | Absent |
| Blueair | Absent | Strong · 109 | Moderate · 41 | Absent | Emerging · 20 |
Frequently asked questions
The corpus covers 15,295 patent families across global jurisdictions. This is the base for trend and technology-composition analysis; applicant rankings are drawn from the top 100 filers within this set.
LG Electronics leads with 608 patent families, ahead of Coway (337), Samsung Electronics (296), Gree Electric Appliance (288), and Donaldson (232).
Annual filings peaked in 2021, following a sharp surge from 2019 through 2021 that likely reflects heightened investment triggered by pandemic-era awareness of indoor air quality risks. Volume has eased since, consistent with a post-peak consolidation phase.
Air conditioning and ventilation (F24F) and separation and filtration processes (B01D) are by far the two largest branches. Sterilisation and disinfection (A61L) is a meaningful but smaller third cluster; electrostatic separation (B03C) and catalysis (B01J) are comparatively sparse.
China is the dominant filing jurisdiction, followed by the United States and South Korea. Europe (EPO) and WIPO PCT filings are also substantial. Any freedom-to-operate assessment must prioritise China given its weight in the data.
Samsung Electronics shows the strongest recent momentum among profiled applicants, with filings up 132% in the most recent three-year window versus the prior three years. Gree Electric Appliance is essentially flat (0%), while LG Electronics and Blueair have contracted significantly (-71% and -81% respectively).
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Disclaimer. This page is generated from PatSnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
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