ALPHA TIER HISTORICAL

Historical DEX Data API

Query delta exposure by strike at any minute since April 2018. Same response shape as the live /v1/exposure/dex endpoint — add at= to replay dealer delta-hedging pressure from any historical moment.

Coverage
2018-04-16 → 2026-04-02
Granularity
1 minute
Tier
Alpha+
Format
JSON (REST)

Endpoint

GET /v1/exposure/dex/{symbol}?at=...
Host: historical.flashalpha.com Auth: X-Api-Key Tier: Alpha
NameInRequiredDefaultDescription
symbolpathyesUnderlying symbol
atqueryyesAs-of timestamp (yyyy-MM-ddTHH:mm:ss ET)
expirationquerynoallFilter to a single expiry (yyyy-MM-dd)
curl -H "X-Api-Key: YOUR_API_KEY" \
  "https://historical.flashalpha.com/v1/exposure/dex/SPY?at=2020-03-16T15:30:00"

Response

{
  "symbol": "SPY",
  "underlying_price": 246.01,
  "as_of": "2020-03-16T15:30:00",
  "as_of_requested": "2020-03-16T15:30:00",
  "payload": {
    "net_dex": -169419489077,
    "strikes": [
      { "strike": 240, "call_dex": 612481.33, "put_dex": -290214.50, "net_dex": 322266.83 }
    ]
  }
}

What This Unlocks

  • Replay dealer delta positioning at any minute — measure actual hedging flow at the open/close of historical moves.
  • Backtest delta-flow strategies with point-in-time data — no lookahead bias.
  • Decompose hedging pressure into delta (DEX) vs gamma (GEX) vs vanna (VEX) vs charm (CHEX) — needed for clean sensitivity analysis.