GAMMA & VOLATILITY$WDCWestern Digital Corp.Open ticker analysis →
Options positioning in Western Digital is stacking up around the $400 strike into Oct 2, 1% below where the stock trades at $403.86. Net gamma reads negative, a setup where hedging can speed moves up instead of slowing them down.
What happened
Across 290 contracts in the Oct 2 expiration, the heaviest gamma sits at $400. Net gamma exposure across the chain comes to roughly $22.75M negative, with about $21.2M of premium traded.
This read uses the standard gamma-map convention, counting call open interest as positive gamma and put open interest as negative. Real dealer books can differ, so treat the sign as a guide to the setup rather than a certainty.
Why it matters
When net gamma is negative, hedging chases the move: market makers buy as the stock rises and sell as it falls. Breaks can travel further and faster than usual in that setup.
For scale, Western Digital is a large-cap computer storage devices company valued near $166.8B, so it takes serious money to move the stock, which is what makes signals like this one worth tracking.
With 1 days left, this is expiration-week territory, when pinning pressure around big strikes is usually at its strongest.
The numbers
| Stock price | $403.86 |
|---|---|
| Expiration | Oct 2 (1 days) |
| Peak gamma strike | $400 |
| Strike vs. stock | 1% below |
| Net gamma exposure | $22.75M (negative) |
| Premium traded | $21.2M |
| Contracts in chain | 290 |
Three ways this could play out
Bullish continuation
If $WDC pushes through $424.05, it breaks away from the $400 cluster. With negative gamma, hedging can add fuel and extend the move.
Bearish rejection
If $WDC drops under $383.67, the $400 cluster stops acting as support. Negative gamma means hedging sells into the drop and can speed it up.
Neutral stabilization
If $WDC hovers near $400 into Oct 2, the cluster does its job and expiration-week pinning becomes the story.
What to watch next
- $400: the peak gamma strike and the most likely pin into expiration.
- Oct 2: expiration, when this positioning rolls off and the magnet effect ends.
- Whether net gamma flips sign as the stock moves. A flip from positive to negative often marks a volatility shift.
