Bitcoin options market reprices risk as September expiry looms
This digest was compiled by AI from multiple sources — links to the originals are below.
Bitcoin's end-of-September options expiry holds 130,670 BTC of open interest, compared with 79,003 BTC for August. The concentration of top strikes mirrors routine quarterly positioning rather than a Federal Reserve bet. End-September calls now trade 0.97 volatility points richer than puts, a swing of nearly six points toward upside in under three weeks.
Key Facts
- September and December quarterly expiries together hold 59.3% of all Bitcoin options open interest.
- The top five strikes account for 31% of September's open interest, the same concentration as December and March.
- Weekly options volume tripled to 64,749 contracts around Aug. 19, the week the US Treasury announced expanded buybacks.
- US-traded spot Bitcoin ETFs took in roughly $1.92 billion last week, their strongest weekly pace of 2026.
- Bitcoin remains up about 22% since Treasury Secretary Scott Bessent said on Aug. 20 that the US would at least double planned purchases of 10- to 30-year debt.
September Expiry Structure
Bitcoin's end-of-September options expiry holds 130,670 BTC of open interest, compared with 79,003 BTC for August. DWF Labs market insights lead Martin Lee said the gap has little to do with the Federal Reserve's Sept. 16 decision. September and December are the two quarterly expiries, and together they hold 59.3% of all open interest because traders often roll positions into them. The top five strikes account for 31% of September's open interest, the same concentration seen in December and March. If September were an aggressive, concentrated bet on the Fed, the book would probably look different from routine quarterly positioning elsewhere on the calendar.
Volume Shift and Treasury Buybacks
The week of July's Fed meeting traded 14,983 contracts, a number Lee described as mid-range for the summer. Weekly volume tripled to 64,749 contracts around Aug. 19, the same week the US Treasury announced it would at least double its long-end liquidity-support buybacks. The Treasury raised the maximum operation size from $2 billion to at least $4 billion starting Sept. 9. Bitcoin ran from $64,100 to a close near $77,000 that week, clearing out roughly $4 billion of short positions along the way. Stanley Druckenmiller has separately criticized the expanded buybacks as damaging to Treasury's credibility.
Call-Put Repricing
Puts had been the richer side of Bitcoin's options market for close to a year. The December expiry printed a negative monthly median every single month from December 2025 through August 2026, with only three positive daily readings across 224 sessions. End-September calls now trade 0.97 volatility points richer than puts, up from 4.96 points cheaper on Aug. 3. US-traded spot Bitcoin ETFs took in roughly $1.92 billion last week, their strongest weekly pace of 2026. Bitcoin advanced 1% on Wednesday to about $79,000 as of 9:20 a.m. in London, after briefly breaking through $81,000 on Tuesday before giving up gains.
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Bitcoin options market reprices risk as September expiry looms
