diff --git a/src/transactions/amm.ts b/src/transactions/amm.ts
index 4f5c67b..49d125e 100644
--- a/src/transactions/amm.ts
+++ b/src/transactions/amm.ts
@@ -254,13 +254,24 @@ export async function authorizeDerivedKeyAMM(
     SellingDAOCoinCreatorPublicKey: string;
     QuoteCurrencyPublicKey: string;
     numSubOrders: number;
+    /**
+     * When buying or selling raw DESO (i.e. QuoteCurrencyPublicKey === 'DESO'),
+     * set this to the total DESO amount (in nanos) that will be spent/received
+     * across all sub-orders so the derived key limit covers the full trade.
+     * Falls back to a hardcoded default when not provided.
+     */
+    GlobalDESOLimitNanos?: number;
   }
 ) {
   const jwt = await identity.jwt();
   const deriveResponse = await identity.derive(
     {
       GlobalDESOLimit:
-        payload.QuoteCurrencyPublicKey === 'DESO' ? 100000 * 1e9 : 1e9,
+        payload.GlobalDESOLimitNanos !== undefined
+          ? payload.GlobalDESOLimitNanos
+          : payload.QuoteCurrencyPublicKey === 'DESO'
+          ? 100000 * 1e9
+          : 1e9,
       TransactionCountLimitMap: {
         AUTHORIZE_DERIVED_KEY: 1,
         // CREATE_USER_ASSOCIATION: payload.numSubOrders,