diff --git a/tests/cases/conformance/classes/classDeclarations/classAndInterfaceMergeConflictingMembers.ts b/tests/cases/conformance/classes/classDeclarations/classAndInterfaceMergeConflictingMembers.ts
new file mode 100644
index 00000000000..d11d67c3fea
--- /dev/null
+++ b/tests/cases/conformance/classes/classDeclarations/classAndInterfaceMergeConflictingMembers.ts
@@ -0,0 +1,23 @@
+declare class C1 {
+    public x : number;
+}
+
+interface C1 {
+    x : number;
+}
+
+declare class C2 {
+    protected x : number;
+}
+
+interface C2 {
+    x : number;
+}
+
+declare class C3 {
+    private x : number;
+}
+
+interface C3 {
+    x : number;
+}
\ No newline at end of file
diff --git a/tests/cases/conformance/classes/classDeclarations/declaredClassMergedwithSelf.ts b/tests/cases/conformance/classes/classDeclarations/declaredClassMergedwithSelf.ts
new file mode 100644
index 00000000000..4688fec9e26
--- /dev/null
+++ b/tests/cases/conformance/classes/classDeclarations/declaredClassMergedwithSelf.ts
@@ -0,0 +1,9 @@
+declare class C1 {}
+
+declare class C1 {}
+
+declare class C2 {}
+
+interface C2 {}
+
+declare class C2 {}
\ No newline at end of file
diff --git a/tests/cases/conformance/classes/classDeclarations/mergedClassInterface.ts b/tests/cases/conformance/classes/classDeclarations/mergedClassInterface.ts
new file mode 100644
index 00000000000..4fac95b516a
--- /dev/null
+++ b/tests/cases/conformance/classes/classDeclarations/mergedClassInterface.ts
@@ -0,0 +1,11 @@
+declare class C1 {}
+
+interface C1 {}
+
+interface C2 {}
+
+declare class C2 {}
+
+interface C2 {}
+
+interface C2 {}
\ No newline at end of file