diff --git a/TestSuite/patterns-extended-is-generic.pas b/TestSuite/patterns-extended-is-generic.pas
new file mode 100644
index 000000000..e5ef3ac65
--- /dev/null
+++ b/TestSuite/patterns-extended-is-generic.pas
@@ -0,0 +1,14 @@
+type
+  t1 = class end;
+  
+procedure p1<T>(l: List<t1>);
+where T: t1;
+begin
+  l.RemoveAll(o->(o is T(var a)));
+end;
+
+begin 
+  var l := Lst(new t1, nil);
+  p1&<t1>(l);
+  assert(l[0] = nil);
+end.
\ No newline at end of file
diff --git a/TreeConverter/TreeConversion/SyntaxTreeVisitorNodes/Patterns.cs b/TreeConverter/TreeConversion/SyntaxTreeVisitorNodes/Patterns.cs
index 01d309297..99dc7da6f 100644
--- a/TreeConverter/TreeConversion/SyntaxTreeVisitorNodes/Patterns.cs
+++ b/TreeConverter/TreeConversion/SyntaxTreeVisitorNodes/Patterns.cs
@@ -126,7 +126,9 @@ namespace PascalABCCompiler.TreeConverter
                 if (genericDeduceNeeded && (candidateParameter.is_generic_parameter || candidateParameter.is_generic_type_instance))
                     candidateParameter = InstantiateParameter(candidateParameter, deducedGenerics);
 
-                if (givenParameter != null && !AreTheSameType(candidateParameter, givenParameter))
+                if (givenParameter != null && !AreTheSameType(candidateParameter, givenParameter)
+                    && !(candidateParameter != null && givenParameter != null && candidateParameter.is_generic_parameter 
+                    && givenParameter.is_generic_parameter && candidateParameter.name == givenParameter.name && givenParameter.base_type == candidateParameter.base_type))
                     return false;
 
                 parameterTypes[i] = candidateParameter;