Set BLP Instrument Subscription

Subscribe the authenticated Backstop Liquidity Provider (BLP) account to an instrument, or unsubscribe it. A participant only receives backstop allocations on the instruments it is subscribed to.

The subscription always applies to the authenticated account — there is no account parameter. Program membership itself is set by Polymarket under the participation agreement and cannot be changed here: an authenticated account that is not enrolled receives a 404, matching GET /v1/blp/enrollment.

Subscribing sets the instrument's leverage to the program leverage of 3x before the subscription takes effect, and the instrument's leverage is then locked for as long as the subscription stands — PATCH /v1/trade/leverage on a subscribed instrument rejects with blp_leverage_locked. The margin mode is left as it is. Unsubscribing releases the lock and leaves the leverage at 3x; set it to whatever you want afterwards.

If the leverage change is rejected (for example the instrument's risk tier caps leverage below 3x), the subscription is not applied and the rejection is returned unchanged.

The call is idempotent — subscribing an already-subscribed instrument, or unsubscribing one that was never subscribed, succeeds and changes nothing. A repeated subscribe leaves the leverage as the first one set it.

{
  "active": true
}