The ranked list covers 100 companies, and no single filer dominates: the top-ranked assignee holds 56 records, with fifth place at 38 and tenth place at 26. The top 5 assignees combined account for only 6.5% of all 3,364 records in scope, and the top 10 combined reach 11.0%. That means most of the field's activity sits with filers outside the ranked leaders, so a competitive review needs to look past the obvious names.

Filing activity peaked at 94 records in 2017 and did not sustain that level afterward, but the most recent complete comparison shows growth, not decline: 39 records in 2021 rose to 51 in 2024, a 31% increase. Figures for 2025 and 2026 look lower, but that reflects normal publication lag of roughly 18 months rather than a real slowdown. Any conclusion about the field cooling off should wait until those later years finish publishing.

Germany is by far the dominant receiving office in this dataset with 1,572 records, ahead of the EPO at 447 and WIPO/PCT filings at 320. The United States (138) and Australia (123) trail well behind. This distribution suggests German patent examiners have built the deepest body of prior art in this specific technology, which matters both for drafting strategy and for where a search should start.

GB201911055D0, filed by Anhui University of Science and Technology on 2019-09-18, describes a gravity casting simulation test bench that pairs a modelled filling and solidification prediction with a physical instrumented rig for validation. It is included here as a representative record of the corpus rather than the most-cited filing in the field. Whether it blocks a specific new filing depends on how closely a proposed claim tracks its particular test-bench and validation-loop architecture, which requires a direct claim-by-claim comparison rather than a landscape-level read.

Filing density is visibly thinner around vacuum-assisted die filling controls, warpage prediction algorithms, die-life estimation under thermal cycling, thermal balance sensing in multi-cavity dies, and air-entrapment detection methods, relative to the core simulation and gating-system claims that dominate the corpus. Thin filing density signals open claim space rather than a technology gap in demand, since these are established engineering problems without heavy patent coverage yet. A first mover drafting claims here has more room to define the architecture than in the more heavily filed gating and filling-pattern space.