Index: clangd/Quality.h
===================================================================
--- clangd/Quality.h
+++ clangd/Quality.h
@@ -87,6 +87,7 @@
   bool Forbidden = false; // Unavailable (e.g const) or inaccessible (private).
   /// Whether fixits needs to be applied for that completion or not.
   bool NeedsFixIts = false;
+  bool InBaseClass = false; // A member from base class of the accessed class.
 
   URIDistance *FileProximityMatch = nullptr;
   /// These are used to calculate proximity between the index symbol and the
Index: clangd/Quality.cpp
===================================================================
--- clangd/Quality.cpp
+++ clangd/Quality.cpp
@@ -299,6 +299,7 @@
                               : 0.6;
     SemaFileProximityScore = std::max(DeclProximity, SemaFileProximityScore);
     IsInstanceMember |= isInstanceMember(SemaCCResult.Declaration);
+    InBaseClass |= SemaCCResult.InBaseClass;
   }
 
   // Declarations are scoped, others (like macros) are assumed global.
@@ -375,6 +376,9 @@
     Score *= 0.5;
   }
 
+  if (InBaseClass)
+    Score *= 0.7;
+
   // Penalize for FixIts.
   if (NeedsFixIts)
     Score *= 0.5;
Index: unittests/clangd/QualityTests.cpp
===================================================================
--- unittests/clangd/QualityTests.cpp
+++ unittests/clangd/QualityTests.cpp
@@ -184,7 +184,13 @@
   // The injected class name is treated as the outer class name.
   Relevance = {};
   Relevance.merge(CodeCompletionResult(&findDecl(AST, "S::S"), 42));
-  EXPECT_EQ(Relevance.Scope, SymbolRelevanceSignals::GlobalScope);
+
+  Relevance = {};
+  EXPECT_FALSE(Relevance.InBaseClass);
+  auto BaseMember = CodeCompletionResult(&findAnyDecl(AST, "y"), 42);
+  BaseMember.InBaseClass = true;
+  Relevance.merge(Member);
+  EXPECT_TRUE(Relevance.InBaseClass);
 }
 
 // Do the signals move the scores in the direction we expect?
@@ -276,6 +282,10 @@
   EXPECT_LT(Instance.evaluate(), Default.evaluate());
   Instance.IsInstanceMember = true;
   EXPECT_EQ(Instance.evaluate(), Default.evaluate());
+
+  SymbolRelevanceSignals InBaseClass;
+  InBaseClass.InBaseClass = true;
+  EXPECT_LT(InBaseClass.evaluate(), Default.evaluate());
 }
 
 TEST(QualityTests, ScopeProximity) {