diff --git a/compatibility_matrices/compatibility_matrix.3.xml b/compatibility_matrices/compatibility_matrix.3.xml
index 0964c99..bca0b37 100644
--- a/compatibility_matrices/compatibility_matrix.3.xml
+++ b/compatibility_matrices/compatibility_matrix.3.xml
@@ -147,7 +147,7 @@
             <regex-instance>.*</regex-instance>
         </interface>
     </hal>
-    <hal format="hidl" optional="false">
+    <hal format="hidl" optional="true">
         <name>android.hardware.drm</name>
         <version>1.1</version>
         <interface>