diff --git a/examples/stock.proto b/examples/stock.proto
index de7ee939..5ee2bcbc 100644
--- a/examples/stock.proto
+++ b/examples/stock.proto
@@ -34,7 +34,7 @@ package examples;
 // Protocol type definitions
 message StockRequest {
   string symbol = 1;
-  int32 num_trades_to_watch = 2 [default=0];
+  int32 num_trades_to_watch = 2;
 }
 
 message StockReply {