diff --git a/DbcParserLib/Dbc.cs b/DbcParserLib/Dbc.cs
index 2e72df8..56ecb1e 100644
--- a/DbcParserLib/Dbc.cs
+++ b/DbcParserLib/Dbc.cs
@@ -11,10 +11,10 @@ public class Dbc
         public IEnumerable<Node> Nodes {get;}
         public IEnumerable<Message> Messages {get;}
         public IEnumerable<EnvironmentVariable> EnvironmentVariables { get; }
-        public IEnumerable<CustomPropertyDefinition> GlobalProperties { get; }
+        public IEnumerable<CustomProperty> GlobalProperties { get; }
 
         public Dbc(IEnumerable<Node> nodes, IEnumerable<Message> messages, IEnumerable<EnvironmentVariable> environmentVariables,
-            IEnumerable<CustomPropertyDefinition> globalProperties)
+            IEnumerable<CustomProperty> globalProperties)
         {
             Nodes = nodes;
             Messages = messages;
diff --git a/DbcParserLib/DbcBuilder.cs b/DbcParserLib/DbcBuilder.cs
index e620879..ab267b2 100644
--- a/DbcParserLib/DbcBuilder.cs
+++ b/DbcParserLib/DbcBuilder.cs
@@ -18,6 +18,7 @@ internal class DbcBuilder : IDbcBuilder
         private readonly IDictionary<uint, Message> m_messages = new Dictionary<uint, Message>();
         private readonly IDictionary<uint, IDictionary<string, Signal>> m_signals = new Dictionary<uint, IDictionary<string, Signal>>();
         private readonly IDictionary<string, EnvironmentVariable> m_environmentVariables = new Dictionary<string, EnvironmentVariable>();
+        private readonly IDictionary<string, CustomProperty> m_globalCustomProperties = new Dictionary<string, CustomProperty>();
 
         private readonly IDictionary<string, ValuesTable> m_namedTablesMap = new Dictionary<string, ValuesTable>();
         private readonly IDictionary<CustomPropertyObjectType, IDictionary<string, CustomPropertyDefinition>> m_customProperties = new Dictionary<CustomPropertyObjectType, IDictionary<string, CustomPropertyDefinition>>() {
@@ -117,6 +118,23 @@ public void AddNodeCustomProperty(string propertyName, string nodeName, string v
                 m_observer.PropertyNameNotFound(propertyName);
         }
 
+        public void AddGlobalCustomProperty(string propertyName, string value, bool isNumeric)
+        {
+            if(m_customProperties[CustomPropertyObjectType.Global].TryGetValue(propertyName, out var customPropertyDefinition))
+            {
+                var property = new CustomProperty(customPropertyDefinition);
+                if(!property.SetCustomPropertyValue(value, isNumeric))
+                    return;
+
+                if(m_globalCustomProperties.TryGetValue(propertyName, out _))
+                    m_observer.DuplicatedGlobalProperty(propertyName);
+                else
+                    m_globalCustomProperties[propertyName] = property;
+            }
+            else
+                m_observer.PropertyNameNotFound(propertyName);
+        }
+
         public void AddEnvironmentVariableCustomProperty(string propertyName, string variableName, string value, bool isNumeric)
         {
             if (m_customProperties[CustomPropertyObjectType.Environment].TryGetValue(propertyName, out var customProperty))
@@ -332,6 +350,35 @@ private void FillNodesNotSetCustomPropertyWithDefault()
             }
         }
 
+        private void FillEnvironmentVariablesNotSetCustomPropertyWithDefault()
+        {
+            var environmentCustomProperties = m_customProperties[CustomPropertyObjectType.Environment];
+            foreach (var customProperty in environmentCustomProperties)
+            {
+                foreach (var envVariable in m_environmentVariables.Values)
+                {
+                    if (!envVariable.CustomProperties.TryGetValue(customProperty.Key, out _))
+                    {
+                        envVariable.CustomProperties[customProperty.Key] = new CustomProperty(customProperty.Value);
+                        envVariable.CustomProperties[customProperty.Key].SetCustomPropertyValueFromDefault();
+                    }
+                }
+            }
+        }
+
+        private void FillGlobalCustomPropertiesNotSetCustomPropertyWithDefault()
+        {
+            var globalCustomProperties = m_customProperties[CustomPropertyObjectType.Global];
+            foreach (var customPropertyPair in globalCustomProperties)
+            {
+                if (!m_globalCustomProperties.TryGetValue(customPropertyPair.Key, out _))
+                {
+                    m_globalCustomProperties[customPropertyPair.Key] = new CustomProperty(customPropertyPair.Value);
+                    m_globalCustomProperties[customPropertyPair.Key].SetCustomPropertyValueFromDefault();
+                }
+            }
+        }
+
         private void FillMessagesNotSetCustomPropertyWithDefault()
         {
             var messageCustomProperties = m_customProperties[CustomPropertyObjectType.Message];
@@ -369,6 +416,8 @@ public Dbc Build()
         {
             FillNodesNotSetCustomPropertyWithDefault();
             FillMessagesNotSetCustomPropertyWithDefault();
+            FillEnvironmentVariablesNotSetCustomPropertyWithDefault();
+            FillGlobalCustomPropertiesNotSetCustomPropertyWithDefault();
 
             foreach (var message in m_messages)
             {
@@ -399,7 +448,7 @@ public Dbc Build()
             //}
             //return new Dbc(nodes, messages, environmentVariables);
 
-            return new Dbc(m_nodes.ToArray(), m_messages.Values.ToArray(), m_environmentVariables.Values.ToArray(), m_customProperties[CustomPropertyObjectType.Global].Values);
+            return new Dbc(m_nodes.ToArray(), m_messages.Values.ToArray(), m_environmentVariables.Values.ToArray(), m_globalCustomProperties.Values);
         }
     }
 
diff --git a/DbcParserLib/IDbcBuilder.cs b/DbcParserLib/IDbcBuilder.cs
index 66dcd7b..17c0046 100644
--- a/DbcParserLib/IDbcBuilder.cs
+++ b/DbcParserLib/IDbcBuilder.cs
@@ -19,6 +19,7 @@ internal interface IDbcBuilder
         void AddCustomProperty(CustomPropertyObjectType objectType, CustomPropertyDefinition customProperty);
         void AddCustomPropertyDefaultValue(string propertyName, string value, bool isNumeric);
         void AddNodeCustomProperty(string propertyName, string nodeName, string value, bool isNumeric);
+        void AddGlobalCustomProperty(string propertyName, string value, bool isNumeric);
         void AddEnvironmentVariableCustomProperty(string propertyName, string variableName, string value, bool isNumeric);
         void AddMessageCustomProperty(string propertyName, uint messageId, string value, bool isNumeric);
         void AddSignalCustomProperty(string propertyName, uint messageId, string signalName, string value, bool isNumeric);
diff --git a/DbcParserLib/Observers/IParseFailureObserver.cs b/DbcParserLib/Observers/IParseFailureObserver.cs
index 8f4639e..003752d 100644
--- a/DbcParserLib/Observers/IParseFailureObserver.cs
+++ b/DbcParserLib/Observers/IParseFailureObserver.cs
@@ -12,6 +12,7 @@ public interface IParseFailureObserver
         void DuplicatedProperty(string propertyName);
         void DuplicatedPropertyInNode(string propertyName, string nodeName);
         void DuplicatedPropertyInEnvironmentVariable(string propertyName, string environmentVariableName);
+        void DuplicatedGlobalProperty(string propertyName);
         void DuplicatedPropertyInMessage(string propertyName, uint messageId);
         void DuplicatedPropertyInSignal(string propertyName, string signalName);
         void DuplicatedEnvironmentVariableInNode(string environmentVariableName, string nodeName);
diff --git a/DbcParserLib/Observers/SilentFailureObserver.cs b/DbcParserLib/Observers/SilentFailureObserver.cs
index 2dd0d16..c50f4ec 100644
--- a/DbcParserLib/Observers/SilentFailureObserver.cs
+++ b/DbcParserLib/Observers/SilentFailureObserver.cs
@@ -36,6 +36,10 @@ public void DuplicatedPropertyInEnvironmentVariable(string propertyName, string
         {
         }
 
+        public void DuplicatedGlobalProperty(string propertyName)
+        {
+        }
+
         public void DuplicatedPropertyInMessage(string propertyName, uint messageId)
         {
         }
diff --git a/DbcParserLib/Observers/SimpleFailureObserver.cs b/DbcParserLib/Observers/SimpleFailureObserver.cs
index 41330e2..abe7db0 100644
--- a/DbcParserLib/Observers/SimpleFailureObserver.cs
+++ b/DbcParserLib/Observers/SimpleFailureObserver.cs
@@ -54,6 +54,11 @@ public void DuplicatedPropertyInEnvironmentVariable(string propertyName, string
             AddError($"Duplicated custom property '{propertyName}' in environment variable '{environmentVariableName}'");
         }
 
+        public void DuplicatedGlobalProperty(string propertyName)
+        {
+            AddError($"Duplicated custom property '{propertyName}' among global properties");
+        }
+
         public void DuplicatedPropertyInMessage(string propertyName, uint messageId)
         {
             AddError($"Duplicated custom property '{propertyName}' in message (ID {messageId})");
diff --git a/DbcParserLib/Parsers/PropertiesLineParser.cs b/DbcParserLib/Parsers/PropertiesLineParser.cs
index 4a09bcb..00b6f9d 100644
--- a/DbcParserLib/Parsers/PropertiesLineParser.cs
+++ b/DbcParserLib/Parsers/PropertiesLineParser.cs
@@ -37,6 +37,10 @@ public bool TryParse(string line, IDbcBuilder builder, INextLineProvider nextLin
                     builder.AddMessageCustomProperty(match.Groups[1].Value, uint.Parse(match.Groups[5].Value, CultureInfo.InvariantCulture), stringValue, isNumeric);
                 else if (match.Groups[6].Value == "SG_")
                     builder.AddSignalCustomProperty(match.Groups[1].Value, uint.Parse(match.Groups[7].Value, CultureInfo.InvariantCulture), match.Groups[8].Value, stringValue, isNumeric);
+                else
+                {
+                    builder.AddGlobalCustomProperty(match.Groups[1].Value, match.Groups[9].Value, isNumeric);
+                }
             }
             else
                 m_observer.PropertySyntaxError();