The assignee ranking covers 100 companies drawn from the full set of 1,051 records, and filing activity is concentrated at the top: the five most active assignees together account for 112 records, or 10.7% of all records in scope, and the ten most active account for 166 records, or 15.8%. Beyond that group the ranking thins into a long tail of single- or few-filing entrants, which is typical of a mature abrasives and machine-tool sector rather than a field with one dominant gatekeeper. Reviewing the leading names alongside their filing dates is a more reliable signal than any single headline number, since concentration at this level still leaves most of the field open.

Annual filings rose to a peak of 45 in 2018 after starting at 13 in 2017, then declined through the following years. The most recent complete year-over-year comparison available, 2021 to 2024, shows a drop from 17 to 12 filings, a 29% decline over that span. Filings shown for 2025 and 2026 should be read as provisional, because publication of a patent application typically lags its filing date by around 18 months, so recent-year counts will continue to rise as more records are published.

B24B, covering grinding and polishing, is by far the largest classification, appearing on 79.0% of the 1,051 records in scope. The next largest are B24D (grinding tools and abrasives, 27.7%) and B23Q (machine tool fittings, 24.6%). Because a single patent record can be tagged with several IPC subclasses, these percentages do not sum to 100%, and each should be read as a standalone share of the full record set rather than combined with the others.

US5103701A, assigned to the United States Department of Energy and granted in 1992, covers diamond machining of materials that chemically react with diamond cutting tools, using cryogenic chilling of both tool and workpiece to suppress that reaction. It blocks the specific combination of diamond-tool machining plus temperature-based reaction suppression on reactive materials, but it does not cover diamond machining generally or reaction-suppression methods that use a different mechanism, such as coatings or atmosphere control. Anyone machining reactive materials with diamond tools should check whether their process relies on cryogenic chilling specifically, since that is the claim's operative mechanism.

The thinner IPC branches — milling (B23C, 4.9% of records), gear and thread cutting (B23F, 4.6%) and cleaning appliances (A47L, 4.5%) — carry far less filing density than the dominant grinding and polishing class (B24B, 79.0%). Co-assignee collaboration is also limited across the dataset, with only 10 co-assignee pairs recorded and the strongest pair linking two divisions of a single abrasives group, suggesting little cross-company claiming in the adjacent branches. A new filing framed around a specific process step in one of these lighter branches, rather than a general diamond-tool claim, is less likely to collide with the dense prior art sitting in grinding and polishing.