diff --git a/java/aar.go b/java/aar.go
index 0fdde03..8a83792 100644
--- a/java/aar.go
+++ b/java/aar.go
@@ -29,8 +29,8 @@
 )
 
 type AndroidLibraryDependency interface {
+	LibraryDependency
 	ExportPackage() android.Path
-	ExportedProguardFlagFiles() android.Paths
 	ExportedRRODirs() []rroDir
 	ExportedStaticPackages() android.Paths
 	ExportedManifests() android.Paths
@@ -498,8 +498,7 @@
 
 	aarFile android.WritablePath
 
-	exportedProguardFlagFiles android.Paths
-	exportedStaticPackages    android.Paths
+	exportedStaticPackages android.Paths
 }
 
 var _ android.OutputFileProducer = (*AndroidLibrary)(nil)
@@ -514,10 +513,6 @@
 	}
 }
 
-func (a *AndroidLibrary) ExportedProguardFlagFiles() android.Paths {
-	return a.exportedProguardFlagFiles
-}
-
 func (a *AndroidLibrary) ExportedStaticPackages() android.Paths {
 	return a.exportedStaticPackages
 }
@@ -566,13 +561,16 @@
 	a.exportedProguardFlagFiles = append(a.exportedProguardFlagFiles,
 		android.PathsForModuleSrc(ctx, a.dexProperties.Optimize.Proguard_flags_files)...)
 	ctx.VisitDirectDeps(func(m android.Module) {
-		if lib, ok := m.(AndroidLibraryDependency); ok && ctx.OtherModuleDependencyTag(m) == staticLibTag {
-			a.exportedProguardFlagFiles = append(a.exportedProguardFlagFiles, lib.ExportedProguardFlagFiles()...)
-			a.exportedStaticPackages = append(a.exportedStaticPackages, lib.ExportPackage())
-			a.exportedStaticPackages = append(a.exportedStaticPackages, lib.ExportedStaticPackages()...)
+		if ctx.OtherModuleDependencyTag(m) == staticLibTag {
+			if lib, ok := m.(LibraryDependency); ok {
+				a.exportedProguardFlagFiles = append(a.exportedProguardFlagFiles, lib.ExportedProguardFlagFiles()...)
+			}
+			if alib, ok := m.(AndroidLibraryDependency); ok {
+				a.exportedStaticPackages = append(a.exportedStaticPackages, alib.ExportPackage())
+				a.exportedStaticPackages = append(a.exportedStaticPackages, alib.ExportedStaticPackages()...)
+			}
 		}
 	})
-
 	a.exportedProguardFlagFiles = android.FirstUniquePaths(a.exportedProguardFlagFiles)
 	a.exportedStaticPackages = android.FirstUniquePaths(a.exportedStaticPackages)
 
diff --git a/java/app.go b/java/app.go
index a822cbf..eb1b474 100755
--- a/java/app.go
+++ b/java/app.go
@@ -457,7 +457,7 @@
 func (a *AndroidApp) proguardBuildActions(ctx android.ModuleContext) {
 	var staticLibProguardFlagFiles android.Paths
 	ctx.VisitDirectDeps(func(m android.Module) {
-		if lib, ok := m.(AndroidLibraryDependency); ok && ctx.OtherModuleDependencyTag(m) == staticLibTag {
+		if lib, ok := m.(LibraryDependency); ok && ctx.OtherModuleDependencyTag(m) == staticLibTag {
 			staticLibProguardFlagFiles = append(staticLibProguardFlagFiles, lib.ExportedProguardFlagFiles()...)
 		}
 	})
diff --git a/java/dex_test.go b/java/dex_test.go
index 6617873..fc6cd0f 100644
--- a/java/dex_test.go
+++ b/java/dex_test.go
@@ -155,3 +155,57 @@
 	android.AssertStringDoesNotContain(t, "expected no  static_lib header jar in foo javac classpath",
 		fooD8.Args["d8Flags"], staticLibHeader.String())
 }
+
+func TestProguardFlagsInheritance(t *testing.T) {
+	result := PrepareForTestWithJavaDefaultModulesWithoutFakeDex2oatd.RunTestWithBp(t, `
+		android_app {
+			name: "app",
+			static_libs: [
+				"primary_android_lib",
+				"primary_lib",
+			],
+			platform_apis: true,
+		}
+
+		java_library {
+			name: "primary_lib",
+			optimize: {
+				proguard_flags_files: ["primary.flags"],
+			},
+		}
+
+		android_library {
+			name: "primary_android_lib",
+			static_libs: ["secondary_lib"],
+			optimize: {
+				proguard_flags_files: ["primary_android.flags"],
+			},
+		}
+
+		java_library {
+			name: "secondary_lib",
+			static_libs: ["tertiary_lib"],
+			optimize: {
+				proguard_flags_files: ["secondary.flags"],
+			},
+		}
+
+		java_library {
+			name: "tertiary_lib",
+			optimize: {
+				proguard_flags_files: ["tertiary.flags"],
+			},
+		}
+	`)
+
+	app := result.ModuleForTests("app", "android_common")
+	appR8 := app.Rule("r8")
+	android.AssertStringDoesContain(t, "expected primary_lib's proguard flags from direct dep",
+		appR8.Args["r8Flags"], "primary.flags")
+	android.AssertStringDoesContain(t, "expected primary_android_lib's proguard flags from direct dep",
+		appR8.Args["r8Flags"], "primary_android.flags")
+	android.AssertStringDoesContain(t, "expected secondary_lib's proguard flags from inherited dep",
+		appR8.Args["r8Flags"], "secondary.flags")
+	android.AssertStringDoesContain(t, "expected tertiary_lib's proguard flags from inherited dep",
+		appR8.Args["r8Flags"], "tertiary.flags")
+}
diff --git a/java/java.go b/java/java.go
index dd24376..5813250 100644
--- a/java/java.go
+++ b/java/java.go
@@ -294,6 +294,11 @@
 	ClassLoaderContexts() dexpreopt.ClassLoaderContextMap
 }
 
+// Provides transitive Proguard flag files to downstream DEX jars.
+type LibraryDependency interface {
+	ExportedProguardFlagFiles() android.Paths
+}
+
 // TODO(jungjw): Move this to kythe.go once it's created.
 type xref interface {
 	XrefJavaFiles() android.Paths
@@ -596,9 +601,17 @@
 type Library struct {
 	Module
 
+	exportedProguardFlagFiles android.Paths
+
 	InstallMixin func(ctx android.ModuleContext, installPath android.Path) (extraInstallDeps android.Paths)
 }
 
+var _ LibraryDependency = (*Library)(nil)
+
+func (j *Library) ExportedProguardFlagFiles() android.Paths {
+	return j.exportedProguardFlagFiles
+}
+
 var _ android.ApexModule = (*Library)(nil)
 
 // Provides access to the list of permitted packages from apex boot jars.
@@ -694,6 +707,15 @@
 		}
 		j.installFile = ctx.InstallFile(installDir, j.Stem()+".jar", j.outputFile, extraInstallDeps...)
 	}
+
+	j.exportedProguardFlagFiles = append(j.exportedProguardFlagFiles,
+		android.PathsForModuleSrc(ctx, j.dexProperties.Optimize.Proguard_flags_files)...)
+	ctx.VisitDirectDeps(func(m android.Module) {
+		if lib, ok := m.(LibraryDependency); ok && ctx.OtherModuleDependencyTag(m) == staticLibTag {
+			j.exportedProguardFlagFiles = append(j.exportedProguardFlagFiles, lib.ExportedProguardFlagFiles()...)
+		}
+	})
+	j.exportedProguardFlagFiles = android.FirstUniquePaths(j.exportedProguardFlagFiles)
 }
 
 func (j *Library) DepsMutator(ctx android.BottomUpMutatorContext) {