ETH's 2800 Call Buy Is Half of a Block Spread, Not a Standalone Bet

The 09-18 ETH 2800 call flagged the platform's top taker-flow z-score (44.1) on a 07:00-08:00 UTC block: 3,000 contracts bought at buyerAggression 1.0, worth roughly $69k in premium. Reading the 24h OI delta alone would suggest simple bullish accumulation — the strike's call OI rose 3,079 contracts on the day. But the tape tells a tighter story.

Strike	Call OI Δ24h	Net Premium (24h)	Buyer Aggr	Block Trades
2700	+1,506	$61,433	0.95	1
2800	+3,079	$63,866	0.93	2
3200	+2,052	-$9,806	0.00	2

The 2800 call's two block buys carry $7.54M in notional; the 3200 call posted two block sells the same session for almost the identical -$7.54M. Aggressor was a buyer on the near strike and a seller on the far one, in matched size — consistent with one call-spread execution rather than a standalone long. The 2700 strike shows genuine independent buying (buyerAggression 0.95, no offsetting mirror), while puts stayed clustered and modest near 2450-2500, well below the call activity in size.