Filing is concentrated at the top: the leading assignee alone accounts for 412 of the 1,900 records in scope, and the top five combined hold 63.9% of all records. Beyond the top ten, which together hold 75.1%, filing volume drops off sharply into a long tail of companies with only a handful of filings each. This pattern suggests that a small group of established crystal growers control most of the core process claims, while smaller filers tend to patent narrower or adjacent improvements.

Filings peaked at 96 records in 2023 and have since eased, with the complete-year comparison showing 49 filings in 2021 falling to 33 in 2024, a -33% change. However, publication typically lags actual filing by around 18 months, so the lower counts recorded for 2025 and 2026 understate real activity and should not be read as a confirmed slowdown yet. A clearer read on the post-2023 trend will only be available once those later years finish publishing.

US7374741B2 claims a Czochralski method that uses a hydrogen-containing ambient gas and a specific pull-rate window chosen to produce a dislocation cluster defect region rather than a laser-scattering-tomography defect region, plus a resulting wafer with a defined LPD density threshold. It does not block every pull-rate strategy — only approaches that match its specific gas composition and defect-region targeting combination. Methods that vary the ambient gas chemistry, target different defect regions, or use different LPD thresholds may sit outside its claim scope, though a freedom-to-operate check against the full claim set is needed before relying on that.