Expiry Positioning Strategy API

Endpoint

GET /v1/strategies/expiry-positioning/{symbol}

Auth required (X-Api-Key) Rate Limited: Yes Basic+

Parameters

Name	In	Required	Default	Description
`symbol`	path	yes	-	Underlying symbol
`expiry`	query	no	nearest upcoming expiry	`yyyy-MM-dd`. The expiry to analyse.
`minOpenInterest`	query	no	`250`	Minimum OI a leg must have to be selected.
`wingWidth`	query	no	`5.0`	Iron-fly wing width, in strike points.

curl -H "X-Api-Key: YOUR_API_KEY" \
  "https://lab.flashalpha.com/v1/strategies/expiry-positioning/SPY?expiry=2026-06-19&wingWidth=5"

import requests

resp = requests.get(
    "https://lab.flashalpha.com/v1/strategies/expiry-positioning/SPY",
    params={"expiry": "2026-06-19", "wingWidth": 5},
    headers={"X-Api-Key": "YOUR_API_KEY"}
)
data = resp.json()
print(f"{data['decision']} (score {data['score']}, regime {data['regime']})")

const resp = await fetch(
  "https://lab.flashalpha.com/v1/strategies/expiry-positioning/SPY?expiry=2026-06-19&wingWidth=5",
  { headers: { "X-Api-Key": "YOUR_API_KEY" } }
);
const data = await resp.json();
console.log(`${data.decision} (score ${data.score}, regime ${data.regime})`);

API Key

Response

Returns the standard strategy decision envelope. The metrics and regime fields are specific to this strategy (see below).

{
  "strategy": "expiry_positioning",
  "symbol": "SPY",
  "timestamp": "2026-06-05T14:32:11Z",
  "decision": "candidate",
  "score": 72,
  "confidence": 0.83,
  "regime": "strong_pin_likely",
  "best_structures": [
    {
      "rank": 1,
      "structure": "iron_fly",
      "expiry": "2026-06-19",
      "legs": [
        { "action": "sell", "type": "put", "strike": 588, "delta": -0.25, "premium": 1.42, "quantity": 1 },
        { "action": "buy",  "type": "put", "strike": 578, "delta": -0.12, "premium": 0.72, "quantity": 1 }
      ],
      "credit": 0.70,
      "debit": null,
      "max_profit": 0.70,
      "max_loss": 9.30,
      "breakevens": [587.30],
      "edge_score": 72,
      "liquidity_score": 0.88
    }
  ],
  "metrics": {
    "max_pain_strike": 590,
    "underlying_price": 589.12
  },
  "risk_flags": [],
  "why": ["Spot is pinned near max pain with concentrated open interest."],
  "avoid_if": ["A directional catalyst pulls spot away from the pin strike."],
  "data_quality": { "score": 90, "warnings": [] }
}

Notable Metrics

Key
`max_pain_strike`
`distance_to_pain_pct`
`oi_concentration_score`
`total_open_interest`
`expiry`
`days_to_expiry`
`gamma_flip`
`call_wall`
`put_wall`
`distance_to_flip_pct`
`spot_position_label`
`underlying_price`

Regime Values

strong_pin_likely
moderate_pin
no_pin_setup

Errors

Status	`error`	When
`400`	`invalid_expiry`	`expiry` is present but not `yyyy-MM-dd`.
`403`	`tier_restricted`	Caller is below the Basic plan.
`404`	`symbol_not_found`	No market data for the symbol.

About

Expiry positioning measures how likely spot is to pin to a strike into an expiry. It combines the max-pain strike and the distance to it, open-interest concentration, and dealer levels (gamma flip, call wall, put wall) into a single pin-risk score and regime.

When a pin looks strong, the strategy proposes an iron fly centred on the pin so the read arrives as a ranked, tradeable structure. Use minOpenInterest and wingWidth to tune leg selection and the wing.

Common Use Cases

Flag likely pins - read regime to find OPEX names where positioning makes a pin into the close likely
Trade only clean signals - act when decision is candidate and skip no_setup reads where positioning is diffuse
Drop in the proposed structure - pull best_structures[] for an iron-fly centred on the max-pain strike
Rank the watchlist - sort by score to compare distance-to-pain and OI concentration across a universe
Size on conviction - scale the clip by score and confidence rather than a fixed lot
Respect the guardrails - honor risk_flags[] and require a clean data_quality before fading toward the pin

Complementary endpoints

Strategy Signals overview - the shared decision envelope across every strategy
Max Pain - the raw pin strike and OI concentration the signal is built on
Zero-DTE - carry the pin read into the same-day session