diff --git a/imagemeta/heif.go b/imagemeta/heif.go
index dd338091..f54346e0 100644
--- a/imagemeta/heif.go
+++ b/imagemeta/heif.go
@@ -210,8 +210,6 @@ func heifReadBoxes(d *heifData, r io.Reader) error {
 			if w > d.Width || h > d.Height {
 				d.Width, d.Height = w, h
 			}
-		case "mdat":
-			return errors.New("mdat box occurred before meta box")
 		default:
 			if err := heifDiscardN(r, boxDataSize); err != nil {
 				return err