diff --git a/bca-token-solidity/contracts/BCA_ERC20_nf.sol b/bca-token-solidity/contracts/BCA_ERC20_nf.sol
index 97ecb99..d892323 100644
--- a/bca-token-solidity/contracts/BCA_ERC20_nf.sol
+++ b/bca-token-solidity/contracts/BCA_ERC20_nf.sol
@@ -21,6 +21,9 @@ contract BCAServiceToken is ERC20, AccessControl {
     constructor(string memory setName, string memory setSymbol, address setMinter, address setBurner)
         ERC20(setName, setSymbol)
     {
+        require(setMinter != address(0), "Invalid minter address");
+        require(setBurner != address(0), "Invalid burner address");
+
         serviceAddress = msg.sender;
         minterAddress = setMinter;
         burnerAddress = setBurner;
diff --git a/bca-token-solidity/contracts/BCA_Service.sol b/bca-token-solidity/contracts/BCA_Service.sol
index bed91bf..5d29fd6 100644
--- a/bca-token-solidity/contracts/BCA_Service.sol
+++ b/bca-token-solidity/contracts/BCA_Service.sol
@@ -25,6 +25,9 @@ contract BCAService is IService, ReentrancyGuard {
 
     constructor(address setProviderAddress, address tokAddress, 
                 uint16 setMaxInstances, uint256 setDayPrice) {
+        require(setProviderAddress != address(0), "Invalid provider address");
+        require(tokAddress != address(0), "Invalid token address");
+
         tokToken = IERC20(tokAddress);
         dayPrice = setDayPrice;
         providerAddress = setProviderAddress;
diff --git a/bca-token-solidity/contracts/BCA_ServiceInstance.sol b/bca-token-solidity/contracts/BCA_ServiceInstance.sol
index c6f394d..92985e8 100644
--- a/bca-token-solidity/contracts/BCA_ServiceInstance.sol
+++ b/bca-token-solidity/contracts/BCA_ServiceInstance.sol
@@ -35,6 +35,10 @@ contract BCAServiceInstance is IServiceInstance, ReentrancyGuard {
     constructor(address setProviderAddress, address tokAddress,
                 address setUserAddress,
                 uint256 setDayPrice) {
+        require(setProviderAddress != address(0), "Invalid provider address");
+        require(tokAddress != address(0), "Invalid token address");
+        require(setUserAddress != address(0), "Invalid user address");
+
         tokToken = IERC20(tokAddress);
         dayPrice = setDayPrice;
         providerAddress = setProviderAddress;
diff --git a/bca-token-solidity/contracts/BCA_ServiceManager.sol b/bca-token-solidity/contracts/BCA_ServiceManager.sol
index 1f4faec..79821b7 100644
--- a/bca-token-solidity/contracts/BCA_ServiceManager.sol
+++ b/bca-token-solidity/contracts/BCA_ServiceManager.sol
@@ -19,6 +19,9 @@ contract BCAServiceManager is IServiceManager, ReentrancyGuard {
     event ServiceDeployed(address contractAddress);
 
     constructor(address setProviderAddress, address tokAddress) {
+        require(setProviderAddress != address(0), "Invalid provider address");
+        require(tokAddress != address(0), "Invalid token address");
+
         tokToken = IERC20(tokAddress);
         providerAddress = setProviderAddress;
     }