Why it matters
Every options trade has a buyer and a seller, so volume alone cannot tell you which side wanted it more. The side does. A fill at the ask means someone paid the price the market was asking, which usually marks a buyer opening or adding to a position. A fill at the bid means someone accepted what the market was bidding, which usually marks a seller.
Combine the side with the contract type and you get direction. A call at the ask is bullish: someone paid up for the right to buy. A put at the ask is bearish: someone paid up for the right to sell. Reverse both at the bid: a call sold at the bid leans bearish or neutral, a put sold at the bid leans bullish. The AA and BB tokens are the same reading with more urgency, because the trade paid through the quote instead of at it. MID fills carry no direction at all.
This is also how the Options Explorer sorts premium into bullish and bearish: calls bought and puts sold are bullish, puts bought and calls sold are bearish, and mid-price fills are left out.
What it does not tell you
- It does not say whether the position is opening or closing. A buyer at the ask might be buying back a short. A seller at the bid might be taking profits on a long. The next morning's open interest is the only confirmation.
- It is read from the quote at that moment. The side is where the print sat against the bid and ask when it happened. Fast markets can make that reading less certain, which is why the feed carries a confidence level behind it.
- Direction is not conviction. A call at the ask for $50,000 and one for $5 million are both bullish. Premium, size and the volume against open interest separate them.
- Spreads muddy it. In a multi-leg trade one leg is bought at the ask and another sold at the bid on purpose. Read the package, not the legs.
What it looks like in the data
On September 10, 2026, one second apart, the same AAPL call strike printed once at the ask and once at the bid.
Both fills: AAPL $340 call, Oct 16, 2026 expiry, Exec SWEEP, with the stock near $323.90. Same strike, same minute, opposite sides. Not a recommendation.
| Time (ET) | Side | Exec | Contracts | Price | Premium | Reading |
|---|---|---|---|---|---|---|
| 12:43:35 pm | A | SWEEP | 3,045 | $4.90 | $1.49M | Buyer paid the ask: bullish |
| 12:43:36 pm | B | SWEEP | 1,521 | $4.95 | $0.75M | Seller took the bid: leans bearish or neutral |
Read together: the second print was at a higher price than the first, yet it reads as the weaker side, because the market had moved up and the seller accepted the bid rather than waiting. Price alone would have told you the opposite. That is the whole point of the side token.
