diff --git a/android/apex.go b/android/apex.go
index fcbd13e..2ac6ed0 100644
--- a/android/apex.go
+++ b/android/apex.go
@@ -350,7 +350,8 @@
 // ApexModuleBase provides the default implementation for the ApexModule interface. APEX-aware
 // modules are expected to include this struct and call InitApexModule().
 type ApexModuleBase struct {
-	ApexProperties ApexProperties
+	ApexProperties     ApexProperties
+	apexPropertiesLock sync.Mutex // protects ApexProperties during parallel apexDirectlyInAnyMutator
 
 	canHaveApexVariants bool
 
@@ -761,18 +762,22 @@
 
 // UpdateDirectlyInAnyApex uses the final module to store if any variant of this module is directly
 // in any APEX, and then copies the final value to all the modules. It also copies the
-// DirectlyInAnyApex value to any direct dependencies with a CopyDirectlyInAnyApexTag dependency
-// tag.
+// DirectlyInAnyApex value to any transitive dependencies with a CopyDirectlyInAnyApexTag
+// dependency tag.
 func UpdateDirectlyInAnyApex(mctx BottomUpMutatorContext, am ApexModule) {
 	base := am.apexModuleBase()
-	// Copy DirectlyInAnyApex and InAnyApex from any direct dependencies with a
+	// Copy DirectlyInAnyApex and InAnyApex from any transitive dependencies with a
 	// CopyDirectlyInAnyApexTag dependency tag.
-	mctx.VisitDirectDeps(func(dep Module) {
-		if _, ok := mctx.OtherModuleDependencyTag(dep).(CopyDirectlyInAnyApexTag); ok {
-			depBase := dep.(ApexModule).apexModuleBase()
+	mctx.WalkDeps(func(child, parent Module) bool {
+		if _, ok := mctx.OtherModuleDependencyTag(child).(CopyDirectlyInAnyApexTag); ok {
+			depBase := child.(ApexModule).apexModuleBase()
+			depBase.apexPropertiesLock.Lock()
+			defer depBase.apexPropertiesLock.Unlock()
 			depBase.ApexProperties.DirectlyInAnyApex = base.ApexProperties.DirectlyInAnyApex
 			depBase.ApexProperties.InAnyApex = base.ApexProperties.InAnyApex
+			return true
 		}
+		return false
 	})
 
 	if base.ApexProperties.DirectlyInAnyApex {