Stream Trades

Public trades for the subscribed markets, or for every market when tickers are omitted, plus retractions of trades the exchange voids.

SEND/ws

Authorization

UDX-Access-KeyAPI key · headerrequired

Opaque API key ID.

UDX-Access-TimestampAPI key · headerrequired

Unix time in milliseconds, within 30 seconds of server time.

UDX-Access-SignatureAPI key · headerrequired

Standard-base64 RSA-PSS/SHA-256 signature with a 32-byte salt. Sign timestamp + "GET" + "/ws"; the upgrade request has no body hash and no idempotency key.

Messages

tradeDeliver one public trade on a subscribed market.

typestringrequired

Identifies one public trade.

sidSubscriptionIdrequired

Exchange-assigned subscription ID whose lifetime is this WebSocket connection.

min 1 · max 9007199254740991

seqSequenceNumberrequired

Gap-detection sequence local to one subscription. It starts at 1 and increments once per frame on that subscription.

min 1 · max 9007199254740991

msgTradePayloadrequired

One public trade.

Show properties

tradeTraderequired

A public trade (match) on a market.

Show properties

trade_idstringrequired

Exchange-assigned trade identifier.

max length 64

tickerTickerrequired

A human-meaningful natural key naming a single-leg or multi-leg market.

min length 1 · max length 128

pricestringrequired

Trade price, in YES dollars.

max length 24 · matches ^[0-9]+(\.[0-9]{1,6})?$

quantitystringrequired

Contracts traded.

max length 24 · matches ^[0-9]+(\.[0-9]{1,2})?$

taker_sidestringrequired

The aggressor (taker) side of the trade.

Allowed:buysell

executed_atstring<date-time>required

When the trade executed.

max length 40

trade_bustedRetract a trade the exchange voided after publication.

typestringrequired

Identifies a voided trade.

sidSubscriptionIdrequired

Exchange-assigned subscription ID whose lifetime is this WebSocket connection.

min 1 · max 9007199254740991

seqSequenceNumberrequired

Gap-detection sequence local to one subscription. It starts at 1 and increments once per frame on that subscription.

min 1 · max 9007199254740991

msgTradeBustedPayloadrequired

Identifies a trade the exchange voided after it was published.

Show properties

trade_idstringrequired

Exchange-assigned identifier of the voided trade.

max length 64

tickerTickerrequired

A human-meaningful natural key naming a single-leg or multi-leg market.

min length 1 · max length 128

Channel Bindings

ws

methodGET

headers

UDX-Access-Keystringrequired

Opaque API key ID.

min length 1 · max length 255

UDX-Access-Timestampstringrequired

Unix time in milliseconds, within 30 seconds of server time.

max length 13 · matches ^[0-9]{13}$

UDX-Access-Signaturestringrequired

Standard-base64 RSA-PSS/SHA-256 signature with a 32-byte salt. Sign timestamp + "GET" + "/ws"; the upgrade request has no body hash and no idempotency key.

min length 1 · max length 1024

Sec-WebSocket-Protocolstringrequired

Negotiated dated WebSocket API version.

Examples

trade

{
  "type": "trade",
  "sid": 9,
  "seq": 1,
  "msg": {
    "trade": {
      "trade_id": "BP1ZQ131E04K",
      "ticker": "UDXCOMBO-EXAMPLE",
      "price": "0.057",
      "quantity": "29.62",
      "taker_side": "sell",
      "executed_at": "2026-09-25T20:15:08.257000Z"
    }
  }
}

trade_busted

{
  "type": "trade_busted",
  "sid": 9,
  "seq": 2,
  "msg": {
    "trade_id": "BP1ZQ131E04K",
    "ticker": "UDXCOMBO-EXAMPLE"
  }
}