diff --git a/dfu/src/main/java/no/nordicsemi/android/dfu/DfuScope.java b/dfu/src/main/java/no/nordicsemi/android/dfu/DfuScope.java
index 66d185c..b8c116b 100644
--- a/dfu/src/main/java/no/nordicsemi/android/dfu/DfuScope.java
+++ b/dfu/src/main/java/no/nordicsemi/android/dfu/DfuScope.java
@@ -2,7 +2,11 @@ package no.nordicsemi.android.dfu;
 
 import androidx.annotation.IntDef;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
 @SuppressWarnings("WeakerAccess")
+@Retention(RetentionPolicy.SOURCE)
 @IntDef(value = {
             DfuServiceInitiator.SCOPE_SYSTEM_COMPONENTS,
             DfuServiceInitiator.SCOPE_APPLICATION
diff --git a/dfu/src/main/java/no/nordicsemi/android/dfu/FileType.java b/dfu/src/main/java/no/nordicsemi/android/dfu/FileType.java
index 4949a98..b9d70b2 100644
--- a/dfu/src/main/java/no/nordicsemi/android/dfu/FileType.java
+++ b/dfu/src/main/java/no/nordicsemi/android/dfu/FileType.java
@@ -2,7 +2,11 @@ package no.nordicsemi.android.dfu;
 
 import androidx.annotation.IntDef;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
 @SuppressWarnings("WeakerAccess")
+@Retention(RetentionPolicy.SOURCE)
 @IntDef(value = {
             DfuBaseService.TYPE_SOFT_DEVICE,
             DfuBaseService.TYPE_BOOTLOADER,