diff --git a/src/JsonApiDotNetCore/Queries/Internal/Parsing/QueryTokenizer.cs b/src/JsonApiDotNetCore/Queries/Internal/Parsing/QueryTokenizer.cs
index 3f49b6c7fe..f050d9f7b0 100644
--- a/src/JsonApiDotNetCore/Queries/Internal/Parsing/QueryTokenizer.cs
+++ b/src/JsonApiDotNetCore/Queries/Internal/Parsing/QueryTokenizer.cs
@@ -87,7 +87,7 @@ public IEnumerable<Token> EnumerateTokens()
                     }
                     else
                     {
-                        if (_textBuffer.Length == 0 && ch == ' ')
+                        if (_textBuffer.Length == 0 && ch == ' ' && !_isInQuotedSection)
                         {
                             throw new QueryParseException("Unexpected whitespace.");
                         }
diff --git a/test/JsonApiDotNetCoreExampleTests/UnitTests/QueryStringParameters/FilterParseTests.cs b/test/JsonApiDotNetCoreExampleTests/UnitTests/QueryStringParameters/FilterParseTests.cs
index b4319447f1..228ddedbb3 100644
--- a/test/JsonApiDotNetCoreExampleTests/UnitTests/QueryStringParameters/FilterParseTests.cs
+++ b/test/JsonApiDotNetCoreExampleTests/UnitTests/QueryStringParameters/FilterParseTests.cs
@@ -67,6 +67,7 @@ public void Reader_Is_Enabled(JsonApiQueryStringParameters parametersDisabled, b
         [InlineData("filter[posts]", "equals(author,'some')", "Attribute 'author' does not exist on resource 'blogPosts'.")]
         [InlineData("filter[posts]", "lessThan(author,null)", "Attribute 'author' does not exist on resource 'blogPosts'.")]
         [InlineData("filter", " ", "Unexpected whitespace.")]
+        [InlineData("filter", "contains(owner.displayName, )", "Unexpected whitespace.")]
         [InlineData("filter", "some", "Filter function expected.")]
         [InlineData("filter", "equals", "( expected.")]
         [InlineData("filter", "equals'", "Unexpected ' outside text.")]
@@ -115,6 +116,9 @@ public void Reader_Read_Fails(string parameterName, string parameterValue, strin
         [InlineData("filter", "equals(title,'Brian O''Quote')", null, "equals(title,'Brian O''Quote')")]
         [InlineData("filter", "equals(title,'!@#$%^&*()-_=+\"''[]{}<>()/|\\:;.,`~')", null, "equals(title,'!@#$%^&*()-_=+\"''[]{}<>()/|\\:;.,`~')")]
         [InlineData("filter", "equals(title,'')", null, "equals(title,'')")]
+        [InlineData("filter", "startsWith(owner.displayName,'GivenName ')", null, "startsWith(owner.displayName,'GivenName ')")]
+        [InlineData("filter", "endsWith(owner.displayName,' Surname')", null, "endsWith(owner.displayName,' Surname')")]
+        [InlineData("filter", "contains(owner.displayName,' ')", null, "contains(owner.displayName,' ')")]
         [InlineData("filter[posts]", "equals(caption,'this, that & more')", "posts", "equals(caption,'this, that & more')")]
         [InlineData("filter[owner.posts]", "equals(caption,'some')", "owner.posts", "equals(caption,'some')")]
         [InlineData("filter[posts.comments]", "equals(createdAt,'2000-01-01')", "posts.comments", "equals(createdAt,'2000-01-01')")]
diff --git a/test/JsonApiDotNetCoreExampleTests/UnitTests/QueryStringParameters/LegacyFilterParseTests.cs b/test/JsonApiDotNetCoreExampleTests/UnitTests/QueryStringParameters/LegacyFilterParseTests.cs
index d16569c941..94e473a7d1 100644
--- a/test/JsonApiDotNetCoreExampleTests/UnitTests/QueryStringParameters/LegacyFilterParseTests.cs
+++ b/test/JsonApiDotNetCoreExampleTests/UnitTests/QueryStringParameters/LegacyFilterParseTests.cs
@@ -37,7 +37,6 @@ public LegacyFilterParseTests()
         [InlineData("filter[author]", "some", "Attribute 'author' does not exist on resource 'blogPosts'.")]
         [InlineData("filter[author.posts]", "some", "Field 'posts' in 'author.posts' must be an attribute or a to-one relationship on resource 'webAccounts'.")]
         [InlineData("filter[unknown.id]", "some", "Relationship 'unknown' in 'unknown.id' does not exist on resource 'blogPosts'.")]
-        [InlineData("filter[author]", " ", "Unexpected whitespace.")]
         [InlineData("filter", "expr:equals(some,'other')", "Field 'some' does not exist on resource 'blogPosts'.")]
         [InlineData("filter", "expr:equals(author,'Joe')", "Attribute 'author' does not exist on resource 'blogPosts'.")]
         [InlineData("filter", "expr:has(author)", "Relationship 'author' must be a to-many relationship on resource 'blogPosts'.")]
@@ -75,6 +74,7 @@ public void Reader_Read_Fails(string parameterName, string parameterValue, strin
         [InlineData("filter[caption]", "isnull:", "equals(caption,null)")]
         [InlineData("filter[caption]", "isnotnull:", "not(equals(caption,null))")]
         [InlineData("filter[caption]", "unknown:some", "equals(caption,'unknown:some')")]
+        [InlineData("filter[caption]", " ", "equals(caption,' ')")]
         [InlineData("filter[author.userName]", "Jack", "equals(author.userName,'Jack')")]
         [InlineData("filter", "expr:equals(caption,'some')", "equals(caption,'some')")]
         [InlineData("filter", "expr:equals(author,null)", "equals(author,null)")]