The assignee ranking in this dataset is led by one company with 7,542 of the 12,526 records in scope, well ahead of the rest of the field. The top five assignees combined hold 78.4% of all records, and the top ten hold 86.9%, so the field is concentrated among a small group of established hygiene product manufacturers rather than spread evenly across many filers. Anyone assessing freedom to operate in this space should start by reviewing the portfolios of those leading assignees before looking at the long tail of smaller filers.

Filing activity peaked in 2017 at 607 records and has declined since, with complete-year data showing a drop from 378 records in 2021 to 220 in 2024 — a 42% fall. However, publication lags filing by roughly 18 months, so 2025 and 2026 figures in any raw trend chart will look artificially low and should not be read as a sudden collapse. The safest reading is that the field has cooled from its mid-2010s peak but is not necessarily inactive, since recent years are still being populated.

An acquisition distribution layer (ADL) sits between the topsheet and the absorbent core in a hygiene product, and its job is to move fluid quickly into the core while reducing rewet — fluid coming back out under pressure. Filings such as US20030093048A1 describe using a high-void-volume ADL to improve strikethrough and rewet performance without changing the core itself, or to allow a thinner or cheaper core to meet the same performance target. Because ADL design interacts directly with core-thinness and gel-blocking claims, it is a frequent subject of both core patents and dedicated layer patents, and searches in this field need to cover both.

The technology composition data shows that 93.4% of records sit under IPC class A61F, the general classification for absorbent articles, while classes covering more specific processing and material approaches — B32B laminates at 5.8%, D04H nonwovens at 3.8%, B01J chemical/physical processing at 1.2%, and B29C plastics shaping at 0.9% — carry much lower filing density. These thinner classes are where narrower, more specific claims around SAP processing, nonwoven acquisition layer formation, and lamination bonding methods are more likely to find open space, rather than in the core absorbent-article architecture itself, which is heavily claimed.

With the top five assignees holding 78.4% of the 12,526 records in scope and the top ten holding 86.9%, this field shows a high degree of concentration among a handful of global manufacturers. Only ten co-assignee pairs appear in the dataset, and one of those pairs is much larger than the rest, indicating that most of the leading filers built their positions independently rather than through joint filings. For a new entrant, this concentration means competitive analysis should focus heavily on a small number of incumbent portfolios rather than a broad landscape of similarly-sized competitors.