diff --git a/README.md b/README.md
index 63603e8..de1b868 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,16 @@ A macOS utility to replace duplicate file data with a copy-on-write clone.
 
 **dedup** `[-PVnvx]` [`-t` **threads**] [`-d` **depth**] [*file ...*]
 
+# WARNING: Block Corruption Risk
+
+APFS cloning deduplicates storage by making all instances of a file reference the same underlying block.
+**If that block becomes corrupted, all cloned instances are affected.**
+This is generally fine for software projects where files can be regenerated or checked out again, 
+but it poses a risk for unique or irreplaceable files.
+
+To mitigate this, ensure you maintain separate backups on different hardware. 
+Cloning **should not** be considered a substitute for a proper backup strategy.
+
 # DESCRIPTION
 
 **dedup** finds files with identical content using the provided *file* arguments.