The dataset ranks 100 companies by patent family count, and the leading assignee holds 66 of the 461 records in scope – more than double the fifth-place holder at 22. The top five assignees combined account for 35.1% of all records, and that concentration extends to 52.5% once the top ten are included. Behind that leading group sits a long tail of companies with only a handful of filings each, which is typical of a mature, process-heavy field where incremental improvements are still patentable but broad process claims are already occupied.

Based on complete-year data, activity is declining: filings dropped from 14 in 2021 to 1 in 2024, a 93% fall across that span, after peaking at 20 filings in 2018. Because patent publication typically lags filing by around 18 months, the very latest years in any dataset will always look artificially low and should not be read as confirming a continued drop. The safest read is that the 2021-2024 window shows a genuine pullback in new filings, while 2025 and 2026 figures are still filling in.

Shaping-of-plastics claims under IPC class B29C appear in 83.9% of the 461 records in scope, making it by far the densest classification in the field. Containers and packaging (B65D) and the plastics-moulding and plastic-product index classes (B29K, B29L) each cover roughly a fifth to a quarter of records, while polymer composition classes (C08L, C08G) and layered products (B32B) are comparatively thin, the latter at just 6.7%. Because a single record can carry multiple IPC classes, these shares add up to more than 100% and should not be summed into a single total.

US20070087214A1, assigned to ExxonMobil Chemical Patents Inc. and published in 2007, covers methods for stretch blow molding polypropylene articles using composite stretch ratios of 6 or less, along with preforms whose axial and radial dimensions are each at least 35% of the corresponding dimension of the finished blow-molded article. It is a process-and-preform-geometry filing rather than a materials patent, so it is most relevant to teams designing preform dimensions or stretch ratio control for polypropylene rather than PET-specific formulations. Anyone working within those stretch-ratio and preform-geometry parameters for polypropylene articles should review it directly rather than relying on a summary, since the exact numeric thresholds define the boundary of what it covers.

The clearest gap sits in layered and multilayer material integration, where B32B claims cover only 6.7% of the 461 records against a much denser 83.9% for core B29C shaping claims. Sub-areas such as infrared-absorber inner-layer formulations, two-stage injection-stretch-blow processing for polypropylene, and cavity-pressure feedback for cycle-rate control also show thinner claim density relative to the core process art. These are not guarantees of patentability, but they indicate where the occupied ground is thinner and a well-drafted claim has more room to stand on its own prior art rather than colliding with an incumbent leader's filings.