diff --git a/lib/bcoin/wallet.js b/lib/bcoin/wallet.js
index cd4106c3..15cb69ce 100644
--- a/lib/bcoin/wallet.js
+++ b/lib/bcoin/wallet.js
@@ -215,14 +215,15 @@ Wallet.prototype.sign = function sign(tx, type, inputs, off) {
   if (!off)
     off = 0;
 
-  // Filter inputs that this wallet own
-  var inputs = inputs || tx.inputs.filter(function(input) {
-    return input.out.tx && this.ownOutput(input.out.tx);
-  }, this);
   var pub = this.getPublicKey();
+  inputs = inputs || tx.inputs;
 
   // Add signature script to each input
   inputs.forEach(function(input, i) {
+    // Filter inputs that this wallet own
+    if (!input.out.tx || !this.ownOutput(input.out.tx))
+      return;
+
     var s = input.out.tx.getSubscript(input.out.index);
     var hash = tx.subscriptHash(off + i, s, type);
     var signature = bcoin.ecdsa.sign(hash, this.key).toDER();