ETH Jun-26 1800P Sheds 3,614 Contracts in 82-Sigma OI Event

A 3,614-contract OI collapse on the ETH Jun-26 $1,800 put (~$5.9M notional, z-score 82.4) triggered detection at 11:30 UTC, less than 21 hours before Jun-26 08:00 UTC expiry. With spot at $1,630, the $1,800 put is 10.4% in the money and carries a delta of −0.987, meaning the unwound position held near-full directional exposure.

Taker flow on ETH-26JUN26-1800-P was buyer-aggressive over the session (aggression ratio 0.654), with three block prints including 438 and 322 contracts bought in back-to-back hourly buckets on Jun 24. The pattern — OI falling while takers buy premium — is consistent with a short-put holder paying to cover rather than a new directional sale.

The broader Jun-26 chain tells a similar story: 24h net premium sits at −$1.73M (seller-dominant), led by block unwinds at deep ITM puts — 2800P (−$809K net), 5000P (−$526K), 3500P (−$359K). Meanwhile OTM calls built aggressively:

Strike	Side	OI Δ (24h)	Taker bias
1725	C	+4,641	—
1675	C	+2,269	buyer (0.73)
1800	P	−4,430	buyer (0.65)
1900	P	−3,817	seller (0.19)

ATM IV sits at the 98th percentile of its 14-day range. The active pin magnet is the $1,600 max-GEX strike, 1.9% below spot; max pain anchors at $2,000, 22.7% above — a wide gap the tape is currently moving away from.