diff --git a/contracts/tokens/EsToken.sol b/contracts/tokens/EsToken.sol
index b72e7e5..010f643 100644
--- a/contracts/tokens/EsToken.sol
+++ b/contracts/tokens/EsToken.sol
@@ -10,6 +10,7 @@ contract EsToken is RestrictedToken, IEsToken {
 
     constructor(string memory _name, string memory _symbol, address _claimableToken) RestrictedToken(_name, _symbol,
         TokenType.ESCROW) {
+        require(_claimableToken != address(0), "ZERO_ADDRESS");
         claimableToken = _claimableToken;
     }
 }
\ No newline at end of file
diff --git a/package.json b/package.json
index 24d22c8..5ac58ff 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@gammaswap/v1-staking",
-  "version": "0.10.8",
+  "version": "0.10.9",
   "description": "Staking contracts for GammaSwapV1 protocol",
   "scripts": {
     "hardhat": "hardhat",
diff --git a/test/foundry/StakingRouter.t.sol b/test/foundry/StakingRouter.t.sol
index 5063e98..850c638 100644
--- a/test/foundry/StakingRouter.t.sol
+++ b/test/foundry/StakingRouter.t.sol
@@ -6,6 +6,7 @@ import "@gammaswap/v1-core/contracts/base/GammaPoolERC20.sol";
 
 import "../../contracts/interfaces/IRewardTracker.sol";
 import "./fixtures/CPMMGammaSwapSetup.sol";
+import "../../contracts/tokens/EsToken.sol";
 
 contract StakingRouterTest is CPMMGammaSwapSetup {
     function setUp() public {
@@ -27,6 +28,14 @@ contract StakingRouterTest is CPMMGammaSwapSetup {
         approveUserForStaking(user2, address(pool2));
     }
 
+    function testEscrowToken() public {
+        EsToken esToken = new EsToken("test token", "TOK1", address(0x123));
+        assertEq(esToken.claimableToken(), address(0x123));
+
+        vm.expectRevert("ZERO_ADDRESS");
+        EsToken esTokenTest = new EsToken("test token", "TOK1", address(0));
+    }
+
     function testStakingContractsAlreadySet() public {
         vm.expectRevert(bytes4(keccak256("GSTokensAlreadySet()")));
         stakingRouter.initializeGSTokens(address(gs), address(esGs), address(esGsb), address(bnGs), address(weth));