diff --git a/src/plugins/clangtools/clangtool.cpp b/src/plugins/clangtools/clangtool.cpp
index fde13609b6d..0ad57ffec7e 100644
--- a/src/plugins/clangtools/clangtool.cpp
+++ b/src/plugins/clangtools/clangtool.cpp
@@ -821,7 +821,7 @@ void ClangTool::loadDiagnosticsFromFiles()
 
     // Show imported
     reset();
-    onNewDiagnosticsAvailable(diagnostics);
+    onNewDiagnosticsAvailable(diagnostics, /*generateMarks =*/ true);
     setState(State::ImportFinished);
 }
 
@@ -1125,10 +1125,10 @@ QSet<Diagnostic> ClangTool::diagnostics() const
     });
 }
 
-void ClangTool::onNewDiagnosticsAvailable(const Diagnostics &diagnostics)
+void ClangTool::onNewDiagnosticsAvailable(const Diagnostics &diagnostics, bool generateMarks)
 {
     QTC_ASSERT(m_diagnosticModel, return);
-    m_diagnosticModel->addDiagnostics(diagnostics);
+    m_diagnosticModel->addDiagnostics(diagnostics, generateMarks);
 }
 
 void ClangTool::updateForCurrentState()
diff --git a/src/plugins/clangtools/clangtool.h b/src/plugins/clangtools/clangtool.h
index 7882245e917..a50a068e66c 100644
--- a/src/plugins/clangtools/clangtool.h
+++ b/src/plugins/clangtools/clangtool.h
@@ -107,7 +107,7 @@ public:
 
     const QString &name() const;
 
-    void onNewDiagnosticsAvailable(const Diagnostics &diagnostics);
+    void onNewDiagnosticsAvailable(const Diagnostics &diagnostics, bool generateMarks);
 
     QAction *startAction() const { return m_startAction; }
     QAction *startOnCurrentFileAction() const { return m_startOnCurrentFileAction; }
diff --git a/src/plugins/clangtools/clangtoolruncontrol.cpp b/src/plugins/clangtools/clangtoolruncontrol.cpp
index 23fce8492b2..4e9c9e2fee9 100644
--- a/src/plugins/clangtools/clangtoolruncontrol.cpp
+++ b/src/plugins/clangtools/clangtoolruncontrol.cpp
@@ -364,8 +364,12 @@ void ClangToolRunWorker::onRunnerFinishedWithSuccess(const QString &filePath)
     } else {
         if (!m_filesNotAnalyzed.contains(filePath))
             m_filesAnalyzed.insert(filePath);
-        if (!diagnostics.isEmpty())
-            tool()->onNewDiagnosticsAvailable(diagnostics);
+        if (!diagnostics.isEmpty()) {
+            // do not generate marks when we always analyze open files since marks from that
+            // analysis should be more up to date
+            const bool generateMarks = !m_runSettings.analyzeOpenFiles();
+            tool()->onNewDiagnosticsAvailable(diagnostics, generateMarks);
+        }
     }
 
     handleFinished();
diff --git a/src/plugins/clangtools/clangtoolsdiagnosticmodel.cpp b/src/plugins/clangtools/clangtoolsdiagnosticmodel.cpp
index 59ce1084ef4..28a63e836ba 100644
--- a/src/plugins/clangtools/clangtoolsdiagnosticmodel.cpp
+++ b/src/plugins/clangtools/clangtoolsdiagnosticmodel.cpp
@@ -102,7 +102,7 @@ QDebug operator<<(QDebug debug, const Diagnostic &d)
                  ;
 }
 
-void ClangToolsDiagnosticModel::addDiagnostics(const Diagnostics &diagnostics)
+void ClangToolsDiagnosticModel::addDiagnostics(const Diagnostics &diagnostics, bool generateMarks)
 {
     const auto onFixitStatusChanged =
         [this](const QModelIndex &index, FixitStatus oldStatus, FixitStatus newStatus) {
@@ -129,7 +129,7 @@ void ClangToolsDiagnosticModel::addDiagnostics(const Diagnostics &diagnostics)
 
         // Add to file path item
         qCDebug(LOG) << "Adding diagnostic:" << d;
-        filePathItem->appendChild(new DiagnosticItem(d, onFixitStatusChanged, this));
+        filePathItem->appendChild(new DiagnosticItem(d, onFixitStatusChanged, generateMarks, this));
     }
 }
 
@@ -284,11 +284,12 @@ static QString fullText(const Diagnostic &diagnostic)
 
 DiagnosticItem::DiagnosticItem(const Diagnostic &diag,
                                const OnFixitStatusChanged &onFixitStatusChanged,
+                               bool generateMark,
                                ClangToolsDiagnosticModel *parent)
     : m_diagnostic(diag)
     , m_onFixitStatusChanged(onFixitStatusChanged)
     , m_parentModel(parent)
-    , m_mark(new DiagnosticMark(diag))
+    , m_mark(generateMark ? new DiagnosticMark(diag) : nullptr)
 {
     if (diag.hasFixits)
         m_fixitStatus = FixitStatus::NotScheduled;
diff --git a/src/plugins/clangtools/clangtoolsdiagnosticmodel.h b/src/plugins/clangtools/clangtoolsdiagnosticmodel.h
index 39bd84dcb65..095d8938353 100644
--- a/src/plugins/clangtools/clangtoolsdiagnosticmodel.h
+++ b/src/plugins/clangtools/clangtoolsdiagnosticmodel.h
@@ -70,6 +70,7 @@ public:
         = std::function<void(const QModelIndex &index, FixitStatus oldStatus, FixitStatus newStatus)>;
     DiagnosticItem(const Diagnostic &diag,
                    const OnFixitStatusChanged &onFixitStatusChanged,
+                   bool generateMark,
                    ClangToolsDiagnosticModel *parent);
     ~DiagnosticItem() override;
 
@@ -112,7 +113,7 @@ class ClangToolsDiagnosticModel : public ClangToolsDiagnosticModelBase
 public:
     ClangToolsDiagnosticModel(QObject *parent = nullptr);
 
-    void addDiagnostics(const Diagnostics &diagnostics);
+    void addDiagnostics(const Diagnostics &diagnostics, bool generateMarks);
     QSet<Diagnostic> diagnostics() const;
 
     enum ItemRole {