The under-the-radar angle headline. Flow-anchored. "The $43B detail in IBIT's options comeback"

IBIT was never supposed to lose Monday and Wednesday weekly expiries for a quarter. CoinGecko data shows it did anyway, because the fund's June assets, around $43.23 billion, fell on the wrong side of MIAX's old $50 billion gate. The exchange's new Tier 2 test, effective Aug. 18, 2026, cut that threshold in half, and BlackRock's iShares Bitcoin Trust is back on the calendar with expirations on Aug. 19, 24, 26 and 31. The under-reported part of this story is the mechanism behind the removal, not the return. MIAX dropped IBIT from its third-quarter list on July 1, 2026, after the ETF held a slot through the first two quarters. Neither the exchange's listing alert nor the SEC notice names which old condition IBIT failed. Per CoinGecko, the balance sheet implies it: BlackRock's historical fund data put IBIT net assets at about $43.23 billion on June 30, under the former $50 billion gate but comfortably above the new $25 billion floor.

The June AUM that tripped the old gate

MIAX's Pearl rule notice, filed Aug. 13, splits qualifying ETFs into two tiers. Tier 1 keeps the legacy tests, above $50 billion in AUM and 10 million monthly options sides, and adds Tuesday and Thursday short-dated expiries. CoinGecko data shows tier 2 halves both gates to $25 billion and 5 million sides but caps the reward at Monday and Wednesday weeklies

What Tuesday and Thursday still cost

The structural read for desks is narrower than the headline. Tier 2 restores two Mondays and two Wednesdays out beyond the current week, P.M.-settled, and MIAX skips any week where the expiry would collide with a standard, monthly or quarterly expiration. Per CoinGecko, iBIT still does not carry Tuesday or Thursday weeklies until it clears the $50 billion / 10 million Tier 1 bar. That gap matters for how bitcoin vol trades. Monday and Wednesday expiries give market makers and option buyers a steadier cadence for pinning and gamma rolls, but the venue-specific change is not a market-wide shift in IBIT options. Neither MIAX nor any exchange has said how the restored dates will move volume or bitcoin volatility. CoinGecko has BTC at $77,870, down 3.11% in 24 hours with 24-hour volume near $36.3 billion.

The 60-day window to Sept. 17

The rule took effect immediately on filing, but that speed cuts both ways. The SEC waived the usual 30-day delay only to retain the authority to suspend the change within 60 days, a review window that runs into mid-October. Comments on the Federal Register notice close Sept. 17, 2026, giving desks a concrete date to watch rather than an open-ended wait. Nothing in the filing guarantees the expiries stick. A suspension in the 60-day window, or a comment-period pushback, would put IBIT back to a single weekly expiry cadence. For now the watchpoint is procedural: whether the SEC lets the Tier 2 test stand through the Sept. 17 comment deadline and the 60-day review that follows it.