It covers patents on microalgal cells or recombinant microalgae where the claims address internal redox and energy bookkeeping — NADH balance, NADPH supply, redox ratio, cofactor recycling, electron transfer, or energy charge — rather than general cultivation or harvesting. In this dataset the scope is further narrowed to filings classified under microorganism culture (C12N1/12), fermentation and enzymatic synthesis (C12P1/00), or microbiological testing (C12Q1/04). A patent describing a mutated strain purely for faster growth, without a redox or cofactor mechanism in the claims, would sit outside this landscape even if it uses the same species.

The ranked list in this dataset contains 8 companies total, not a top-50 cut — it is the full set the search returns. The leading assignee holds 4 of the 18 records in scope, with the fifth-ranked assignee close behind at 3, so the field has a leader but not a runaway concentration. Two co-assignee pairs, each linking 3 shared records, show that some of the strongest activity is joint work between research institutions and commercial partners rather than any single company acting alone.

Reading only complete years, filings grew from 1 in 2021 to 2 in 2024, a +100% increase over that span, after an earlier peak of 6 in 2019. Counts for 2025 and 2026 appear low, but that reflects the roughly 18-month lag between when an application is filed and when it publishes, not a genuine drop in activity. Any assessment of whether the field is heating up or cooling off should rely on the 2021-2024 window rather than the most recent one or two years shown in a raw trend chart.