diff --git a/src/MDRequirementsSet.php b/src/MDRequirementsSet.php
index a41558c..e24bbd2 100644
--- a/src/MDRequirementsSet.php
+++ b/src/MDRequirementsSet.php
@@ -24,7 +24,10 @@ final class MDRequirementsSet {
     const MIN_OBJECT_IMAGE_HEIGHT = 540;
 
     const TIME_EARLIEST_YEAR = -6000000000;
+    const TIME_EARLIEST_DATE = '0001-01-01';
     const TIME_LATEST_YEAR = 2099;
+    const TIME_LATEST_DATE = '9999-12-31';
+    const TIME_DEFAULT_DATE = '0001-01-01'; // Date to ignore in indexing
 
     const MIMETYPES_USER_PROFILE_IMG = ['image/jpeg', 'image/jpg'];