Delta Exposure (DEX) API

What Is Delta Exposure?

Delta exposure (DEX) measures the net directional position that options dealers hold. When net DEX is positive, dealers are net long delta — they've accumulated shares as hedges. When net DEX is negative, dealers are short the underlying. Unlike GEX (which measures hedging acceleration), DEX captures the absolute directional tilt. Large shifts in DEX can precede directional moves, as dealer hedging activity feeds back into the underlying's supply and demand.

Common Use Cases

• Directional bias detection — positive DEX means dealers are long, indicating call-heavy positioning; negative DEX means put-heavy
• Mean-reversion setups — extreme DEX readings often mark stretched positioning that can unwind
• Sector rotation signals — compare DEX across symbols to spot where directional conviction is concentrating
• Earnings positioning — track DEX buildup before events to see which direction the market is betting
• Multi-exposure analysis — combine DEX with GEX to distinguish between directional and volatility regimes

When to Use This Endpoint

Use the DEX endpoint when you need to understand directional positioning by strike. For gamma (hedging acceleration), use GEX. For a combined snapshot of all four exposures, use the Summary endpoint. DEX is most useful alongside GEX — positive GEX with negative DEX suggests dealers are dampening moves while positioned bearishly.

Endpoint

curl -H "X-Api-Key: YOUR_API_KEY" \
  "https://lab.flashalpha.com/v1/exposure/dex/SPY"

import requests

resp = requests.get(
    "https://lab.flashalpha.com/v1/exposure/dex/SPY",
    headers={"X-Api-Key": "YOUR_API_KEY"}
)
data = resp.json()
print(f"Net DEX: ${data['net_dex']:,.0f}")

const resp = await fetch(
  "https://lab.flashalpha.com/v1/exposure/dex/SPY",
  { headers: { "X-Api-Key": "YOUR_API_KEY" } }
);
const data = await resp.json();
console.log(`Net DEX: $${data.net_dex.toLocaleString()}`);

Response

{
  "symbol": "SPY",
  "underlying_price": 597.505,
  "as_of": "2026-02-28T16:30:45Z",
  "net_dex": -450000000,
  "strikes": [
    {
      "strike": 575.0,
      "call_dex": 5600000,
      "put_dex": 4200000,
      "net_dex": 9800000
    }
  ]
}

Key Response Fields