Bitcoin nears third straight monthly gain, threatening a September pattern since 2013
In brief
- Bitcoin was up about 7% in September after gaining 25% in August, per CoinDesk.
- Every positive August since 2013 was followed by a negative September, CoinDesk said.
- A positive close would leave Q3 up more than 40%, the first positive quarter since Q3 2025.
- A reported Anthropic IPO and the U.S. midterms are November tests, CoinDesk flagged.
A pattern that's held since 2013
The streak comes from CoinDesk's analysis. By its count, every positive August for bitcoin since 2013 has been followed by a negative September. This year's August was a big one (a 25% move), and the month that followed is still green with two calendar days to go.
So does the pattern finally break?
The quarter matters too. A positive September close would leave bitcoin's third quarter up more than 40%, CoinDesk said, which would be its first positive quarter since Q3 2025. CoinDesk also noted that the fourth quarter has historically been bitcoin's strongest, citing CoinGlass data that puts the average Q4 gain at roughly 77%.
The macro backdrop, though, is volatile.
Yields, oil and gold
Bitcoin was trading at $84,000 as of CoinDesk's Sept. 29 report. Bond yields were rising globally, with the U.S. 10-year Treasury yield above 5.2%, and the MOVE index (a measure of bond market volatility) sat above 100, approaching its year-to-date highs.
Commodities weren't calm either. Oil held above $90 a barrel, adding to inflation concerns, while gold fell about 3% on Monday to just above $4,000 an ounce, CoinDesk reported.
Two November tests
CoinDesk said Q4 would bring two further tests for liquidity and risk appetite. The first is Anthropic's reported plan for a November IPO, which CoinDesk said could draw investor attention and capital toward a major new equity listing. The offering's timing and size haven't been finalized.
The second is the U.S. midterm elections, also in November. They could add further volatility as investors assess the policy outlook, according to CoinDesk. It's a crowded calendar for a market that's coming off three months of gains, if September closes green.
Frequently asked questions
What September streak is bitcoin on track to break?
According to CoinDesk, every positive August for bitcoin since 2013 has been followed by a negative September. Bitcoin gained 25% in August and was up about 7% in September with two calendar days left, so a positive close would break that pattern.
What November events could test bitcoin in Q4?
CoinDesk pointed to two tests for liquidity and risk appetite. One is Anthropic's reported plan for a November IPO, which could draw capital toward a major equity listing (its timing and size haven't been finalized). The other is the U.S. midterm elections, which could add volatility.
