The assignee ranking in this dataset is dominated by a single early lineage that reaches 959 records, far ahead of the fifth-place assignee at 69 and the tenth-place assignee at 36. Co-assignee data shows this lineage is really a small, tightly linked group of individual inventor-assignees filed together, which is common for early-2000s genomics-era portfolios that later moved into yeast host-cell engineering. Corporate filers such as Novartis and Danstar Ferment AG appear further down the ranking with narrower, more recent phenotype-specific claims. Anyone assessing freedom to operate should treat the top cluster as one prior-art block rather than several independent filers.

Using only complete-year data, filings fell from 9 in 2021 to 2 in 2024, a 78% drop, after peaking at 11 in 2023. Publication lags filing by roughly 18 months, so the 2025 and 2026 counts in the raw data are still filling in and should not be read as evidence of a continued decline. Taken together, the pattern is a real pullback through the last complete year rather than a field that has stopped moving. A fresh pull closer to the 2026 cut-off will be needed to see whether filing has resumed.

This filing, assigned to Danstar Ferment AG, claims genetic modifications that improve sulfite tolerance in recombinant yeast host cells, specifically through expression of a heterologous transcription factor that favours SSU1 polypeptide expression, or expression of a heterologous SSU1 polypeptide itself. It blocks approaches that rely on that specific transcription-factor-to-SSU1 mechanism for sulfite tolerance in yeast hosts. It does not block sulfite tolerance achieved through unrelated mechanisms, nor does it touch other transporter functions such as product export or general membrane permeability, so the practical scope is narrower than the phenotype it targets.