1 files changed, 2 insertions, 1 deletions
diff --git a/src/ts/0x.js.ts b/src/ts/0x.js.ts
index 89d049bec..d189b48b1 100644
--- a/src/ts/0x.js.ts
+++ b/src/ts/0x.js.ts
@@ -1,6 +1,7 @@
 import * as BigNumber from 'bignumber.js';
 import * as ethUtil from 'ethereumjs-util';
 import {assert} from './utils/assert';
+import {ECSignatureSchema} from './schemas/ec_signature_schema';
 
 /**
  * Elliptic Curve signature
@@ -21,7 +22,7 @@ export class ZeroEx {
      */
     public static isValidSignature(dataHex: string, signature: ECSignature, signer: ETHAddressHex): boolean {
         assert.isHexString('dataHex', dataHex);
-        assert.isObject('signature', signature);
+        assert.doesConformToSchema('signature', signature, ECSignatureSchema);
         assert.isETHAddressHex('signer', signer);
 
         const dataBuff = ethUtil.toBuffer(dataHex);