The takeaway
BillionToOne, Inc. Class A Common Stock shows a pronounced seasonal pattern over 1 years of data — strongest in November (+19.5%) and softest in December (−27.6%).
Right now
Not enough July history yet to summarize.
The full picture
BillionToOne, Inc. Class A Common Stock's most dependable month has been November, higher in 1 of 1 years; December has been its least reliable, up just 0% of the time.
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Win rate % | — | — | — | — | — | — | — | — | — | — | ||
| Median return % | — | — | — | — | — | — | — | — | — | — | ||
| 2025 | — | — | — | — | — | — | — | — | — | — |
Month by month
The stock's clearest edge over the S&P 500 lands in November (+17.2 pts); it has trailed the market most in December (−28.6 pts).
“vs S&P” is BillionToOne, Inc. Class A Common Stock’s average for a month minus the S&P 500’s average for that same month — isolating BillionToOne, Inc. Class A Common Stock’s own seasonal edge from broad market drift.
Reality check
Not enough recent November history to say whether the pattern still holds.
Figures are the typical (median) November return and how often it rose — the last 1 years versus the last 1(the heatmap’s default window). This verdict stays anchored to that 1-year window even if you zoom the chart, so it never disagrees with the badges above.
In plain English
The seasonal story is really one month's story — November. It has closed higher in all 1 Novembers, a concentration the rest of the calendar can't touch.
The strength looks broad-based rather than freakish: its average (+19.5%) and median (+19.5%) sit close together, so no single blow-out year is flattering the figure. No month is steadier: November's returns vary by just 0.0% year to year, and even its worst November in 1 years lost only 19.5% — the gentlest downside anywhere on its calendar. Better still, that strength is the stock's own and not just a buoyant market — November has outpaced the S&P 500 by +17.2 points on average. Few peers keep such company in November — the typical stock clears it just 62% of the time.
No other month comes close to matching it — the rest of the calendar is unremarkable by comparison. On the other side of the ledger, December has been the soft spot — the only month to average an outright loss (−27.6%), and the edge isn't year-round — the stock has trailed the S&P 500 in December. Its roughest month on record was a −27.6% December in 2025 — a reminder of how hard even a seasonal name can fall.
For a stock this dependable in November, the sharper question is the rest of the year — outside its strong stretch, the calendar gives far less to lean on. With a short 1-year record, the signal is best held loosely.
Short answers on the stock's best month (November), its worst (December), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2025 its best month (November, +19.5%) has run well ahead of its worst (December, −27.6%) — the heatmap above shows how steady that gap has been year to year.
November has been the strongest, averaging +19.5% and closing higher in its one year on record since 2025.
It's the weakest, averaging −27.6% — historically a soft spot, though it still varies from year to year.
Explore
These names have the strongest July track records on record — a starting point for comparison.
Before you trade