diff --git a/packages/protocol/contracts/identity/IdentityProxyHub.sol b/packages/protocol/contracts/identity/IdentityProxyHub.sol
index 4256d2ba3ae..4525e338543 100644
--- a/packages/protocol/contracts/identity/IdentityProxyHub.sol
+++ b/packages/protocol/contracts/identity/IdentityProxyHub.sol
@@ -1,15 +1,27 @@
 pragma solidity ^0.5.13;
 
 import "../common/Create2.sol";
+import "../common/interfaces/ICeloVersionedContract.sol";
 import "../common/UsingRegistry.sol";
 import "./IdentityProxy.sol";
 
-contract IdentityProxyHub is UsingRegistry {
+contract IdentityProxyHub is UsingRegistry, ICeloVersionedContract {
   bytes32 public constant identityProxyCodeHash = keccak256(
     // solhint-disable-next-line indent
     abi.encodePacked(type(IdentityProxy).creationCode)
   );
 
+  /**
+   * @notice Returns the storage, major, minor, and patch version of the contract.
+   * @return Storage version of the contract.
+   * @return Major version of the contract.
+   * @return Minor version of the contract.
+   * @return Patch version of the contract.
+   */
+  function getVersionNumber() external pure returns (uint256, uint256, uint256, uint256) {
+    return (1, 0, 0, 1);
+  }
+
   /**
    * @notice Returns the IdentityProxy address corresponding to the identifier.
    * @param identifier The identifier whose proxy address is computed.
@@ -99,7 +111,7 @@ contract IdentityProxyHub is UsingRegistry {
     payable
     returns (bytes memory)
   {
-    require(passesIdentityHeuristic(msg.sender, identifier));
+    require(passesIdentityHeuristic(msg.sender, identifier), "does not pass identity heuristic");
     return getOrDeployIdentityProxy(identifier).makeCall.value(msg.value)(destination, data);
   }
 
diff --git a/packages/protocol/contracts/stability/SortedOracles.sol b/packages/protocol/contracts/stability/SortedOracles.sol
index 4c35ce5404d..b5dd428f5d0 100644
--- a/packages/protocol/contracts/stability/SortedOracles.sol
+++ b/packages/protocol/contracts/stability/SortedOracles.sol
@@ -62,7 +62,7 @@ contract SortedOracles is ISortedOracles, ICeloVersionedContract, Ownable, Initi
    * @return Patch version of the contract.
    */
   function getVersionNumber() external pure returns (uint256, uint256, uint256, uint256) {
-    return (1, 1, 2, 1);
+    return (1, 1, 2, 2);
   }
 
   /**
@@ -171,7 +171,7 @@ contract SortedOracles is ISortedOracles, ICeloVersionedContract, Ownable, Initi
    * @return The address of the last report.
    */
   function isOldestReportExpired(address token) public view returns (bool, address) {
-    require(token != address(0));
+    require(token != address(0), "token address cannot be null");
     address oldest = timestamps[token].getTail();
     uint256 timestamp = timestamps[token].getValue(oldest);
     // solhint-disable-next-line not-rely-on-time