The assignee ranking covers 100 companies counted by patent family, and it is heavily front-loaded: the leader alone holds 80 of the 457 records in scope, and the top five combined account for 43.5% of all records. Below the top ten, which together hold 62.6%, the field spreads into a long tail of companies with only one or a few filings each. This shape means a freedom-to-operate review should focus first on the leading handful of assignees rather than treating the field as evenly distributed.

Annual filings rose to a peak of 26 records in 2018 and have declined since, with the 2021-to-2024 span — the most recent period that can be treated as complete — showing a -100% change. Publication lags filing by roughly 18 months, so the 2025 and 2026 counts in the dataset are still incomplete and should not be read as proof the decline continues. Overall the trend points to a technology whose core claim space was staked out earlier in the period covered.

Container and packaging-structure claims classified under B65D appear on 60.0% of the 457 records, making it the dominant classification. Food preservation methods (A23B, 41.6%) and food and beverage applications (A23L, 31.9%) form the next tier, with packaging and wrapping processes (B65B, 24.5%) also well represented. Material analysis and testing (G01N) and polymer processing (C08J) each cover only a small share, suggesting the sensing and materials side of the field is comparatively open.

US20020020151A1, assigned to Pactiv, claims a method and apparatus for inserting an oxygen scavenger into a modified atmosphere package, including the scavenger feeding, separating, adhesive-application and conveyor mechanisms used to attach a scavenger to an outer film layer. It is a mechanism-and-process patent, not a broad claim over oxygen scavengers or MAP generally, so it is most relevant to anyone designing an automated in-line scavenger-insertion system rather than to MAP packaging or scavenger chemistry as a whole. A design that inserts scavengers by a materially different mechanical route, or that pre-integrates the scavenger into the film rather than attaching it in-line, sits outside its specific claim scope.

The classification data shows structural packaging claims (B65D) far outweighing material analysis and testing (G01N, 6.1%) and polymer processing (C08J, 2.0%), which points to sensing, indicator and advanced-material angles as comparatively under-claimed relative to packaging structure itself. The long tail below the top ten assignees, who hold 62.6% of the 457 records between them, also indicates room for new entrants outside the leading group. Co-filing is limited to ten identified pairs, so there is little evidence of crowded joint-venture activity blocking a solo filer from entering these adjacent branches.