diff --git a/Common/SecurityIdentifier.cs b/Common/SecurityIdentifier.cs
index 629f8ac92c0a..ef70c94d25bb 100644
--- a/Common/SecurityIdentifier.cs
+++ b/Common/SecurityIdentifier.cs
@@ -336,7 +336,7 @@ public SecurityIdentifier(string symbol, ulong properties)
             {
                 throw new ArgumentException(Messages.SecurityIdentifier.PropertiesDoNotMatchAnySecurityType, nameof(properties));
             }
-            _hashCode = Math.Abs(unchecked (symbol.GetHashCode() * 397) ^ properties.GetHashCode());
+            _hashCode = unchecked (symbol.GetHashCode() * 397) ^ properties.GetHashCode();
             _hashCodeSet = true;
         }
 
@@ -1060,7 +1060,7 @@ public override int GetHashCode()
         {
             if (!_hashCodeSet)
             {
-                _hashCode = Math.Abs(unchecked(_symbol.GetHashCode() * 397) ^ _properties.GetHashCode());
+                _hashCode = unchecked(_symbol.GetHashCode() * 397) ^ _properties.GetHashCode();
                 _hashCodeSet = true;
             }
             return _hashCode;