Bitcoin options show downside convexity ahead of FOMC meeting

Bitcoin traders are quietly bracing for impact. Options markets heading into the September 15-16 FOMC meeting showed a clear put skew, meaning implied volatility on 25-delta puts ran higher than the equivalent calls. When protection costs more than participation, the market is telling you something.

The gap was not dramatic, but it was deliberate. The 25-delta put skew for the September 25 expiry came in about 1.44 percentage points above comparable calls, according to positioning data from the period.

When puts carry higher implied volatility than calls at the same delta, market makers are pricing in asymmetric demand: more buyers want downside protection than upside exposure at equivalent strike distances from spot.

In this case, Bitcoin was trading near $80,000 heading into mid-September, and the broader options surface reflected cautious sentiment rather than outright panic. Overall implied volatility, as tracked by the DVOL index on Deribit, sat around 38.9% for near-term contracts on September 16. That is a moderate reading, not the kind of elevated fear gauge you see during genuine liquidation spirals.

Open interest told a similar two-sided story. Calls still dominated, comprising roughly 61% of total open interest versus 39% for puts. The put skew existed not because bears had taken over the book, but because a meaningful subset of traders was willing to pay a premium for insurance on short-dated contracts specifically.