diff --git a/ets2panda/linter/src/lib/TypeScriptLinter.ts b/ets2panda/linter/src/lib/TypeScriptLinter.ts
index 99cce1c98424fc43371285b4e0611b550ac811b1..e60a5a89f536d5f7a4a327c085304e13a4ddd037 100644
--- a/ets2panda/linter/src/lib/TypeScriptLinter.ts
+++ b/ets2panda/linter/src/lib/TypeScriptLinter.ts
@@ -3676,6 +3676,10 @@ export class TypeScriptLinter extends BaseTypeScriptLinter {
     const baseReturnType = this.tsTypeChecker.getTypeAtLocation(baseMethod.type);
     const derivedReturnType = this.tsTypeChecker.getTypeAtLocation(derivedMethod.type);
 
+    if (this.isDerivedTypeAssignable(derivedReturnType, baseReturnType)) {
+        return;
+    }
+
     if (!this.isTypeAssignable(derivedReturnType, baseReturnType)) {
       this.incrementCounters(derivedMethod.type, FaultID.MethodInheritRule);
     }
@@ -3714,6 +3718,9 @@ export class TypeScriptLinter extends BaseTypeScriptLinter {
 
   // Checks structural assignability between two types.
   private isTypeAssignable(fromType: ts.Type, toType: ts.Type): boolean {
+    if (this.isDerivedTypeAssignable(fromType, toType)) {
+        return true;
+    }
     const fromTypes = this.flattenUnionTypes(fromType);
     const toTypes = new Set(this.flattenUnionTypes(toType));
 
@@ -3723,6 +3730,35 @@ export class TypeScriptLinter extends BaseTypeScriptLinter {
     });
   }
 
+   private isDerivedTypeAssignable(derivedType: ts.Type, baseType: ts.Type): boolean {
+    const baseSymbol = baseType.getSymbol();
+    const derivedSymbol = derivedType.getSymbol();
+
+    if (!baseSymbol || !derivedSymbol) {
+       return false;
+    }
+    const baseDeclarations = baseSymbol.getDeclarations();
+    const derivedDeclarations = derivedSymbol.getDeclarations();
+
+    if (!baseDeclarations || !derivedDeclarations) { 
+      return false;
+    }
+    const baseTypeNode = baseDeclarations[0];
+    const derivedTypeNode = derivedDeclarations[0];
+
+    if (ts.isClassDeclaration(baseTypeNode) && ts.isClassDeclaration(derivedTypeNode)) {
+      const baseTypes = this.tsTypeChecker.getTypeAtLocation(derivedTypeNode).getBaseTypes();
+      const baseTypesExtends = baseTypes?.some((t) => { 
+        return t === baseType; 
+      });
+      if (baseTypesExtends) {
+        return true;
+      }
+    }
+      
+    return false;
+  }
+
   // Converts union types into an array of type strings for easy comparison.
   private flattenUnionTypes(type: ts.Type): string[] {
     if (type.isUnion()) {
diff --git a/ets2panda/linter/test/main/method_inheritance.ets b/ets2panda/linter/test/main/method_inheritance.ets
index c92fa1f0d9d509516fdbe3eabe31b71fee67282c..5a40e9462b56cc77b00a88a9b5f4ebfbff26328c 100644
--- a/ets2panda/linter/test/main/method_inheritance.ets
+++ b/ets2panda/linter/test/main/method_inheritance.ets
@@ -216,3 +216,18 @@ class Derived4 implements  Base3 {
     return new A1();
   }
 }
+
+class Animal {}
+class Dog extends Animal {}
+
+class Base6 {
+  public foo(): Animal {
+    console.log("base")
+  }
+}
+// extends
+class Derived6 extends Base6 {
+  public foo(): Dog {      // no error
+    console.log("Derived:")
+  }
+}
\ No newline at end of file