diff --git a/contracts/libraries/Claimable.sol b/contracts/libraries/Claimable.sol
index 39d40a9b..e77dc009 100644
--- a/contracts/libraries/Claimable.sol
+++ b/contracts/libraries/Claimable.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.5.2;
+pragma solidity ^0.5.12;
 
 /**
  * @title Claimable
diff --git a/contracts/libraries/Compare.sol b/contracts/libraries/Compare.sol
index 7001804f..674c9143 100644
--- a/contracts/libraries/Compare.sol
+++ b/contracts/libraries/Compare.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.5.2;
+pragma solidity ^0.5.12;
 
 library Compare {
 
diff --git a/contracts/libraries/ERC20WithFees.sol b/contracts/libraries/ERC20WithFees.sol
index fc823f49..9665cfd8 100644
--- a/contracts/libraries/ERC20WithFees.sol
+++ b/contracts/libraries/ERC20WithFees.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.5.2;
+pragma solidity ^0.5.12;
 
 import "openzeppelin-solidity/contracts/token/ERC20/IERC20.sol";
 import "openzeppelin-solidity/contracts/token/ERC20/SafeERC20.sol";
diff --git a/contracts/libraries/String.sol b/contracts/libraries/String.sol
index 95151ce6..c981115d 100644
--- a/contracts/libraries/String.sol
+++ b/contracts/libraries/String.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.5.2;
+pragma solidity ^0.5.12;
 
 library String {
 
diff --git a/contracts/libraries/Validate.sol b/contracts/libraries/Validate.sol
index 8a93d20a..31d41970 100644
--- a/contracts/libraries/Validate.sol
+++ b/contracts/libraries/Validate.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.5.8;
+pragma solidity ^0.5.12;
 
 import "openzeppelin-solidity/contracts/cryptography/ECDSA.sol";
 
diff --git a/contracts/test/CompareTest.sol b/contracts/test/CompareTest.sol
index d6c65256..be7b142f 100644
--- a/contracts/test/CompareTest.sol
+++ b/contracts/test/CompareTest.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.5.2;
+pragma solidity ^0.5.12;
 
 import { Compare } from "../libraries/Compare.sol";
 
diff --git a/contracts/test/StringTest.sol b/contracts/test/StringTest.sol
index 95488240..73c678d5 100644
--- a/contracts/test/StringTest.sol
+++ b/contracts/test/StringTest.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.5.2;
+pragma solidity ^0.5.12;
 
 import { String } from "../libraries/String.sol";
 
diff --git a/contracts/test/ValidateTest.sol b/contracts/test/ValidateTest.sol
index 8384eea1..8d306e3d 100644
--- a/contracts/test/ValidateTest.sol
+++ b/contracts/test/ValidateTest.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.5.8;
+pragma solidity ^0.5.12;
 
 import "../libraries/Validate.sol";