diff --git a/src/interfaces/IStablecoinDEX.sol b/src/interfaces/IStablecoinDEX.sol
index b4fdd31..344e86a 100644
--- a/src/interfaces/IStablecoinDEX.sol
+++ b/src/interfaces/IStablecoinDEX.sol
@@ -63,6 +63,16 @@ interface IStablecoinDEX {
     event OrderFilled(
         uint128 indexed orderId, address indexed maker, address indexed taker, uint128 amountFilled, bool partialFill
     );
+    event OrderFlipped(
+        uint128 indexed orderId,
+        address indexed maker,
+        address indexed token,
+        uint128 amount,
+        bool isBid,
+        int16 tick,
+        bool isFlipOrder,
+        int16 flipTick
+    );
     event OrderPlaced(
         uint128 indexed orderId,
         address indexed maker,