diff --git a/analysis/analysis-api-providers/src/org/jetbrains/kotlin/analysis/providers/KotlinAnchorModuleProvider.kt b/analysis/analysis-api-providers/src/org/jetbrains/kotlin/analysis/providers/KotlinAnchorModuleProvider.kt
index 0597ac1e467..a10634add6e 100644
--- a/analysis/analysis-api-providers/src/org/jetbrains/kotlin/analysis/providers/KotlinAnchorModuleProvider.kt
+++ b/analysis/analysis-api-providers/src/org/jetbrains/kotlin/analysis/providers/KotlinAnchorModuleProvider.kt
@@ -10,17 +10,22 @@ import org.jetbrains.kotlin.analysis.project.structure.KtLibraryModule
 import org.jetbrains.kotlin.analysis.project.structure.KtSourceModule
 
 /**
- * Provide module which contains dependencies of the library.
+ * [KotlinAnchorModuleProvider] provides modules which contain dependencies of libraries.
  *
- * Is required for navigation in IJ monorepo from kotlin compiler library sources to IJ platform sources.
- * Kotlin compiler depends on platform but this dependency is not represented as jars in monorepo
- * but should be replaced with given sources.
+ * In the IJ monorepo, anchor modules are required for navigation from Kotlin compiler library sources to IJ platform sources. The Kotlin
+ * compiler depends on the IJ platform, but this dependency is not represented as JARs in the monorepo, but rather by certain monorepo
+ * source modules, which are made visible to the Kotlin compiler library sources as dependencies via an anchor module.
  */
 public interface KotlinAnchorModuleProvider {
     public fun getAnchorModule(libraryModule: KtLibraryModule): KtSourceModule?
 
+    /**
+     * Returns all anchor modules configured in the project.
+     */
+    public fun getAllAnchorModules(): Collection<KtSourceModule>
+
     public companion object {
         public fun getInstance(project: Project): KotlinAnchorModuleProvider? =
             project.getService(KotlinAnchorModuleProvider::class.java)
     }
-}
\ No newline at end of file
+}
diff --git a/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionInvalidationService.kt b/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionInvalidationService.kt
index 6aa8171f831..5f8f97d41fe 100644
--- a/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionInvalidationService.kt
+++ b/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionInvalidationService.kt
@@ -9,6 +9,7 @@ import com.intellij.openapi.Disposable
 import com.intellij.openapi.application.ApplicationManager
 import com.intellij.openapi.project.Project
 import org.jetbrains.kotlin.analysis.project.structure.*
+import org.jetbrains.kotlin.analysis.providers.KotlinAnchorModuleProvider
 import org.jetbrains.kotlin.analysis.providers.analysisMessageBus
 import org.jetbrains.kotlin.analysis.providers.topics.*
 
@@ -87,6 +88,17 @@ class LLFirSessionInvalidationService(private val project: Project) : Disposable
     private fun invalidateAll(includeStableModules: Boolean) {
         ApplicationManager.getApplication().assertWriteAccessAllowed()
 
+        // When anchor modules are configured and `includeStableModules` is `false`, we get a situation where the anchor module session will
+        // be invalidated (because it is a source session), while its library dependents won't be invalidated (because they are sessions of
+        // stable modules). But such library sessions also need to be invalidated because they depend on the anchor module.
+        //
+        // Invalidating anchor modules before all source sessions has the advantage that `invalidate`'s session existence check will work,
+        // so we do not have to invalidate dependent sessions if the anchor module does not exist in the first place.
+        if (!includeStableModules) {
+            val anchorModules = KotlinAnchorModuleProvider.getInstance(project)?.getAllAnchorModules()
+            anchorModules?.forEach(::invalidate)
+        }
+
         LLFirSessionCache.getInstance(project).removeAllSessions(includeStableModules)
     }