diff --git a/src/HtmlAgilityPack.Shared/HtmlDocument.cs b/src/HtmlAgilityPack.Shared/HtmlDocument.cs
index d97fa23d..32656b80 100644
--- a/src/HtmlAgilityPack.Shared/HtmlDocument.cs
+++ b/src/HtmlAgilityPack.Shared/HtmlDocument.cs
@@ -1867,7 +1867,7 @@ private void PushAttributeNameStart(int index, int lineposition)
             _currentattribute.Line = _line;
             _currentattribute._lineposition = lineposition;
             _currentattribute._streamposition = index;
-            _currentattribute.InternalQuoteType = AttributeValueQuote.WithoutValue;
+            //_currentattribute.InternalQuoteType = AttributeValueQuote.WithoutValue;
         }
 
         private void PushAttributeValueEnd(int index)
diff --git a/src/HtmlAgilityPack.Shared/HtmlNode.cs b/src/HtmlAgilityPack.Shared/HtmlNode.cs
index dd4ce703..c8dfd7c4 100644
--- a/src/HtmlAgilityPack.Shared/HtmlNode.cs
+++ b/src/HtmlAgilityPack.Shared/HtmlNode.cs
@@ -2415,7 +2415,24 @@ internal void WriteAttribute(TextWriter outText, HtmlAttribute att)
 			var isWithoutValue = quoteType == AttributeValueQuote.WithoutValue;
 
             string name;
-			string quote = quoteType == AttributeValueQuote.DoubleQuote ? "\"" : quoteType == AttributeValueQuote.SingleQuote ? "'" : "";
+            string quote;
+            switch (quoteType)
+            {
+                case AttributeValueQuote.DoubleQuote:
+                case AttributeValueQuote.Initial:
+                case AttributeValueQuote.WithoutValue:
+                    quote = "\"";
+                    break;
+                case AttributeValueQuote.SingleQuote:
+                    quote = "'";
+                    break;
+                case AttributeValueQuote.None:
+                default:
+                    quote = "";
+                    break;
+            }
+
+			
             if (_ownerdocument.OptionOutputAsXml)
 			{
 				if(quoteType != AttributeValueQuote.DoubleQuote && quoteType != AttributeValueQuote.SingleQuote)
@@ -2457,24 +2474,26 @@ internal void WriteAttribute(TextWriter outText, HtmlAttribute att)
 					}
 				}
 
-				if (!isWithoutValue)
-				{
-					var value = quoteType == AttributeValueQuote.DoubleQuote ? !att.Value.StartsWith("@") ? att.Value.Replace("\"", """) :
-				   att.Value : quoteType == AttributeValueQuote.SingleQuote ?  att.Value.Replace("'", "'") : att.Value;
-					if (_ownerdocument.OptionOutputOptimizeAttributeValues)
-						if (att.Value.IndexOfAny(new char[] {(char) 10, (char) 13, (char) 9, ' '}) < 0)
-							outText.Write(" " + name + "=" + att.Value);
-						else
-							outText.Write(" " + name + "=" + quote + value + quote);
-					else
-						outText.Write(" " + name + "=" + quote + value + quote);
-				}
-				else
+                if (isWithoutValue)
                 {
-					outText.Write(" " + name);
-				}
-
-			}
+                    outText.Write(" " + name);
+                }
+                else
+                {
+                    var value = quoteType == AttributeValueQuote.DoubleQuote
+                        ? !att.Value.StartsWith("@") ? att.Value.Replace("\"", "&quot;") : att.Value
+                        : quoteType == AttributeValueQuote.SingleQuote
+                            ? att.Value.Replace("'", "&#39;")
+                            : att.Value;
+                    if (_ownerdocument.OptionOutputOptimizeAttributeValues)
+                        if (att.Value.IndexOfAny(new char[] { (char)10, (char)13, (char)9, ' ' }) < 0)
+                            outText.Write(" " + name + "=" + att.Value);
+                        else
+                            outText.Write(" " + name + "=" + quote + value + quote);
+                    else
+                        outText.Write(" " + name + "=" + quote + value + quote);
+                }
+            }
 		}
 
 		internal void WriteAttributes(TextWriter outText, bool closing)
diff --git a/src/Tests/HtmlAgilityPack.Tests.NetStandard2_0/HtmlDocument.PreserveOriginalTest.cs b/src/Tests/HtmlAgilityPack.Tests.NetStandard2_0/HtmlDocument.PreserveOriginalTest.cs
index 02ead6fa..fdd37ae1 100644
--- a/src/Tests/HtmlAgilityPack.Tests.NetStandard2_0/HtmlDocument.PreserveOriginalTest.cs
+++ b/src/Tests/HtmlAgilityPack.Tests.NetStandard2_0/HtmlDocument.PreserveOriginalTest.cs
@@ -161,6 +161,31 @@ public void PreserveClonedEmptyAttributesTest()
             Assert.Equal(@"<list-counter formErrorsCounter></list-counter>", cloned.OuterHtml);
         }
 
+        [Fact]
+        public void PreserveEmptyAttributesWithInitialTest()
+        {
+            var d = new HtmlDocument();
+            d.LoadHtml("<bar ng-app class='message'></bar>");
+
+            var node = d.DocumentNode.SelectSingleNode("//bar");
+            var outer = node.OuterHtml;
+
+            Assert.Equal("<bar ng-app=\"\" class='message'></bar>", outer);
+        }
+
+        [Fact]
+        public void PreserveEmptyAttributes()
+        {
+            var d = new HtmlDocument { GlobalAttributeValueQuote = AttributeValueQuote.Initial };
+            d.LoadHtml("<li ng>Nothing to show</li>");
+
+            var node = d.DocumentNode.SelectSingleNode("//li");
+            var outer = node.OuterHtml;
+
+            Assert.Equal($"<li ng=\"\">Nothing to show</li>", outer);
+        }
+
+
         [Fact]
         public void PreserveQuoteTypeForLoadedAttributes()
         {
@@ -173,5 +198,30 @@ public void PreserveQuoteTypeForLoadedAttributes()
             // Result is: QuoteType: WithoutValue
             Assert.Equal(AttributeValueQuote.WithoutValue, checkedAttribute.QuoteType);
         }
+
+        [Fact]
+        public void PreserveQuoteTypeForLoadedAttributes2()
+        {
+            var d = new HtmlDocument { GlobalAttributeValueQuote = AttributeValueQuote.Initial };
+            d.LoadHtml(@"<bar ng-app ng-app2='message'></bar>");
+
+            var node = d.DocumentNode.SelectSingleNode("//bar");
+            var outer = node.OuterHtml;
+
+            Assert.Equal($"<bar ng-app=\"\" ng-app2='message'></bar>", outer);
+        }
+
+        [Fact]
+        public void PreserveQuoteTypeForLoadedAttributes3()
+        {
+            var input = HtmlNode.CreateNode(@"<bar ng-app ng-app2='message'></bar>");
+            var firstAttribute = input.Attributes.First();
+            var secondAttribute = input.Attributes.LastOrDefault();
+            
+            Assert.Equal("", firstAttribute.Value);
+            Assert.Equal(AttributeValueQuote.DoubleQuote, firstAttribute.QuoteType);
+            Assert.Equal("message", secondAttribute.Value);
+            Assert.Equal(AttributeValueQuote.SingleQuote, secondAttribute.QuoteType);
+        }
     }
 }
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