diff --git a/contracts/ControllerV1.sol b/contracts/ControllerV1.sol
index 104efed..a871108 100644
--- a/contracts/ControllerV1.sol
+++ b/contracts/ControllerV1.sol
@@ -99,6 +99,10 @@ contract ControllerV1 is
         uint256 expectedPodId,
         string memory _imageUrl
     ) external override {
+        require(_members.length > 0, "cannot have 0 members");
+        require(threshold > 0, "threshold must be more than 0");
+        require(_label != bytes32(0), "label cannot be blank");
+        require(bytes(_ensString).length > 0, "ensString cannot be empty");
         address safe = createSafe(_members, threshold, expectedPodId);
 
         _createPod(
diff --git a/contracts/MemberTeller.sol b/contracts/MemberTeller.sol
index ebba679..b91c933 100644
--- a/contracts/MemberTeller.sol
+++ b/contracts/MemberTeller.sol
@@ -33,6 +33,8 @@ contract MemberTeller {
 
     function memberTellerCheck(uint256 podId, bytes memory data) internal {
         if (bytes4(data) == ENCODED_SIG_ADD_OWNER) {
+            // Ensure data is at minimum, the length required for the below logic.
+            require(data.length >= 24, "incorrect data length");
             address mintMember;
             assembly {
                 // shift 0x4 for the sig + 0x20 padding
@@ -41,6 +43,8 @@ contract MemberTeller {
             memberToken.mint(mintMember, podId, getSyncData());
         }
         if (bytes4(data) == ENCODED_SIG_REMOVE_OWNER) {
+            // Ensure data is at minimum, the length required for the below logic.
+            require(data.length >= 44, "incorrect data length");
             address burnMember;
             assembly {
                 // note: consecutive addresses are packed into a single memory slot
@@ -51,6 +55,8 @@ contract MemberTeller {
             memberToken.burn(burnMember, podId);
         }
         if (bytes4(data) == ENCODED_SIG_SWAP_OWNER) {
+            // Ensure data is at minimum, the length required for the below logic.
+            require(data.length >= 64, "incorrect data length");
             address burnMember;
             address mintMember;
             assembly {
diff --git a/contracts/MemberToken.sol b/contracts/MemberToken.sol
index d2a2c47..798273a 100644
--- a/contracts/MemberToken.sol
+++ b/contracts/MemberToken.sol
@@ -38,6 +38,10 @@ contract MemberToken is ERC1155Supply, Ownable {
 
     // Note that OpenSea does not currently update contract metadata when this value is changed. - Nov 2021
     function setContractURI(string memory newContractURI) public onlyOwner {
+        require(
+            bytes(newContractURI).length > 0,
+            "newContractURI cannot be empty"
+        );
         _contractURI = newContractURI;
     }
 
diff --git a/contracts/MultiCreateV1.sol b/contracts/MultiCreateV1.sol
index 70dc315..2d6688f 100644
--- a/contracts/MultiCreateV1.sol
+++ b/contracts/MultiCreateV1.sol
@@ -8,6 +8,7 @@ contract MultiCreateV1 {
     IMemberToken immutable memberToken;
 
     constructor(address _memberToken) {
+        require(_memberToken != address(0), "member token can't be 0 address");
         memberToken = IMemberToken(_memberToken);
     }
 
@@ -26,7 +27,9 @@ contract MultiCreateV1 {
         string[] memory _imageUrls
     ) public returns (address[] memory) {
         uint256 numPods = _thresholds.length;
+        require(numPods > 0, "can't call with 0 pods");
         require(_members.length == numPods, "incorrect members array");
+        require(_admins.length == numPods, "incorrect admins array");
         require(_labels.length == numPods, "incorrect labels array");
         require(_ensStrings.length == numPods, "incorrect ensStrings array");
         require(_imageUrls.length == numPods, "incorrect imageUrls array");
diff --git a/contracts/PermissionManager.sol b/contracts/PermissionManager.sol
index 9abcc53..f5433b8 100644
--- a/contracts/PermissionManager.sol
+++ b/contracts/PermissionManager.sol
@@ -1,6 +1,7 @@
 pragma solidity ^0.8.7;
 
 import "openzeppelin-contracts/access/AccessControl.sol";
+import "openzeppelin-contracts/utils/Address.sol";
 
 // This contract will be the owner of all other contracts in the ecosystem.
 contract PermissionManager is AccessControl {
@@ -13,6 +14,7 @@ contract PermissionManager is AccessControl {
         public
         onlyRole(DEFAULT_ADMIN_ROLE)
     {
+        Address.isContract(contractAddress);
         // Call uses the context of this contract, so msg.sender of other contracts
         // will be this contract.
         (bool success, ) = contractAddress.call(data);
diff --git a/contracts/SafeTeller.sol b/contracts/SafeTeller.sol
index ec80faf..cbfefd1 100644
--- a/contracts/SafeTeller.sol
+++ b/contracts/SafeTeller.sol
@@ -42,6 +42,9 @@ contract SafeTeller {
         address _gnosisMasterAddress,
         address _fallbackHanderAddress
     ) {
+        require(_proxyFactoryAddress != address(0), "Invalid address");
+        require(_gnosisMasterAddress != address(0), "Invalid address");
+        require(_fallbackHanderAddress != address(0), "Invalid address");
         proxyFactoryAddress = _proxyFactoryAddress;
         gnosisMasterAddress = _gnosisMasterAddress;
         fallbackHandlerAddress = _fallbackHanderAddress;
@@ -62,6 +65,8 @@ contract SafeTeller {
             _newSafeTeller
         );
 
+        require(_newSafeTeller != address(0), "safe teller can't be 0 address");
+
         bool enableSuccess = IGnosisSafe(_safe).execTransactionFromModule(
             _safe,
             0,
diff --git a/contracts/ens/IPodEnsRegistrar.sol b/contracts/ens/IPodEnsRegistrar.sol
index 3dfca96..a72282d 100644
--- a/contracts/ens/IPodEnsRegistrar.sol
+++ b/contracts/ens/IPodEnsRegistrar.sol
@@ -17,8 +17,6 @@ interface IPodEnsRegistrar {
 
     function register(bytes32 label, address owner) external;
 
-    function deregister(address safe, bytes32 label) external;
-
     function setText(
         bytes32 node,
         string calldata key,