diff --git a/modules/sdk-core/src/bitgo/defi/defiVault.ts b/modules/sdk-core/src/bitgo/defi/defiVault.ts
index 63071f38f3..e26700d9de 100644
--- a/modules/sdk-core/src/bitgo/defi/defiVault.ts
+++ b/modules/sdk-core/src/bitgo/defi/defiVault.ts
@@ -220,12 +220,39 @@ export class DefiVault implements IDefiVault {
   }
 
   /**
-   * Extract operationId from the intent of a sendMany result.
-   * The WP populates operationId in the intent of the approve txRequest.
+   * Extract operationId from a sendMany result.
+   *
+   * The WP writes the defi-service-minted operationId into the built
+   * transaction's `coinSpecific` (alongside `assignedNonce`), not into the
+   * intent. Read it from there: the `full` apiVersion surfaces it at
+   * `transactions[0].unsignedTx.coinSpecific.operationId`, the `lite` version
+   * at `unsignedTxs[0].coinSpecific.operationId`. Fall back to
+   * `intent.operationId` for forward-compat in case the WP later also
+   * populates the intent.
    */
   private extractOperationId(sendManyResult: Record<string, unknown>): string | undefined {
     const txRequest = sendManyResult.txRequest as Record<string, unknown> | undefined;
-    const intent = txRequest?.intent as Record<string, unknown> | undefined;
+    if (!txRequest) {
+      return undefined;
+    }
+
+    // full apiVersion: transactions[0].unsignedTx.coinSpecific.operationId
+    const transactions = txRequest.transactions as Array<Record<string, unknown>> | undefined;
+    const fullUnsignedTx = transactions?.[0]?.unsignedTx as Record<string, unknown> | undefined;
+    const fullCoinSpecific = fullUnsignedTx?.coinSpecific as Record<string, unknown> | undefined;
+    if (fullCoinSpecific?.operationId) {
+      return fullCoinSpecific.operationId as string;
+    }
+
+    // lite apiVersion: unsignedTxs[0].coinSpecific.operationId
+    const unsignedTxs = txRequest.unsignedTxs as Array<Record<string, unknown>> | undefined;
+    const liteCoinSpecific = unsignedTxs?.[0]?.coinSpecific as Record<string, unknown> | undefined;
+    if (liteCoinSpecific?.operationId) {
+      return liteCoinSpecific.operationId as string;
+    }
+
+    // forward-compat: intent.operationId (in case the WP later populates the intent)
+    const intent = txRequest.intent as Record<string, unknown> | undefined;
     return intent?.operationId as string | undefined;
   }
 
diff --git a/modules/sdk-core/test/unit/bitgo/defi/defiVault.ts b/modules/sdk-core/test/unit/bitgo/defi/defiVault.ts
index 6a4377c920..d23f81ab53 100644
--- a/modules/sdk-core/test/unit/bitgo/defi/defiVault.ts
+++ b/modules/sdk-core/test/unit/bitgo/defi/defiVault.ts
@@ -56,16 +56,20 @@ describe('DefiVault', function () {
 
       // Mock sendMany for approve and deposit
       const sendManyStub = sinon.stub(wallet, 'sendMany');
+      // WP writes operationId into the built tx's coinSpecific (full apiVersion),
+      // not into the intent — mirror that real shape here.
       sendManyStub.onFirstCall().resolves({
         txRequest: {
           txRequestId: 'txreq-approve-1',
-          intent: { intentType: 'defi-approve', operationId },
+          intent: { intentType: 'defi-approve' },
+          transactions: [{ unsignedTx: { coinSpecific: { operationId } } }],
         },
       });
       sendManyStub.onSecondCall().resolves({
         txRequest: {
           txRequestId: 'txreq-deposit-1',
-          intent: { intentType: 'defi-deposit', operationId },
+          intent: { intentType: 'defi-deposit' },
+          transactions: [{ unsignedTx: { coinSpecific: { operationId } } }],
         },
       });
 
@@ -91,6 +95,65 @@ describe('DefiVault', function () {
       depositArgs.defiParams.operationId.should.equal(operationId);
     });
 
+    it('should extract operationId from the lite apiVersion coinSpecific', async function () {
+      const operationId = 'op-uuid-lite';
+
+      const sendManyStub = sinon.stub(wallet, 'sendMany');
+      sendManyStub.onFirstCall().resolves({
+        txRequest: {
+          txRequestId: 'txreq-approve-lite',
+          intent: { intentType: 'defi-approve' },
+          unsignedTxs: [{ coinSpecific: { operationId } }],
+        },
+      });
+      sendManyStub.onSecondCall().resolves({
+        txRequest: { txRequestId: 'txreq-deposit-lite' },
+      });
+
+      const result = await defiVault.depositToVault({ vaultId: 'vlt-galaxy-usdc', amount: '1000000' });
+
+      result.operationId.should.equal(operationId);
+      const depositArgs: any = sendManyStub.secondCall.args[0];
+      depositArgs.defiParams.operationId.should.equal(operationId);
+    });
+
+    it('should fall back to intent.operationId for forward-compat', async function () {
+      const operationId = 'op-uuid-intent';
+
+      const sendManyStub = sinon.stub(wallet, 'sendMany');
+      sendManyStub.onFirstCall().resolves({
+        txRequest: {
+          txRequestId: 'txreq-approve-intent',
+          intent: { intentType: 'defi-approve', operationId },
+        },
+      });
+      sendManyStub.onSecondCall().resolves({
+        txRequest: { txRequestId: 'txreq-deposit-intent' },
+      });
+
+      const result = await defiVault.depositToVault({ vaultId: 'vlt-galaxy-usdc', amount: '1000000' });
+
+      result.operationId.should.equal(operationId);
+    });
+
+    it('should throw when operationId is absent from the approve txRequest', async function () {
+      const sendManyStub = sinon.stub(wallet, 'sendMany');
+      sendManyStub.onFirstCall().resolves({
+        txRequest: {
+          txRequestId: 'txreq-approve-missing',
+          intent: { intentType: 'defi-approve' },
+          transactions: [{ unsignedTx: { coinSpecific: {} } }],
+        },
+      });
+
+      await assert.rejects(() => defiVault.depositToVault({ vaultId: 'vlt-galaxy-usdc', amount: '1000000' }), {
+        message: 'operationId not found in approve txRequest response',
+      });
+
+      // Deposit sendMany must not be issued when the operationId is missing
+      sendManyStub.calledOnce.should.be.true();
+    });
+
     // TODO(CGD-1709): Re-enable when active operation pre-flight check is restored
     xit('should reject when an active operation already exists', async function () {
       const preflightReq = mockRequest({
@@ -116,7 +179,8 @@ describe('DefiVault', function () {
       sendManyStub.onFirstCall().resolves({
         txRequest: {
           txRequestId: 'txreq-approve-2',
-          intent: { intentType: 'defi-approve', operationId },
+          intent: { intentType: 'defi-approve' },
+          transactions: [{ unsignedTx: { coinSpecific: { operationId } } }],
         },
       });
       sendManyStub.onSecondCall().rejects(new Error('deposit creation failed'));
@@ -148,13 +212,15 @@ describe('DefiVault', function () {
       sendManyStub.onFirstCall().resolves({
         txRequest: {
           txRequestId: 'txreq-approve-3',
-          intent: { intentType: 'defi-approve', operationId },
+          intent: { intentType: 'defi-approve' },
+          transactions: [{ unsignedTx: { coinSpecific: { operationId } } }],
         },
       });
       sendManyStub.onSecondCall().resolves({
         txRequest: {
           txRequestId: 'txreq-deposit-3',
-          intent: { intentType: 'defi-deposit', operationId },
+          intent: { intentType: 'defi-deposit' },
+          transactions: [{ unsignedTx: { coinSpecific: { operationId } } }],
         },
       });