diff --git a/NewMutableEncodingDesign.md b/NewMutableEncodingDesign.md
index 0f88a20..8ffcb92 100644
--- a/NewMutableEncodingDesign.md
+++ b/NewMutableEncodingDesign.md
@@ -183,7 +183,7 @@ is present in all caps, it's easy to insert arbitrary intermediate levels. It
 doesn't even change the way the existing caps are used:
 
  * (1K) writecap = K-bit random string = privkey
- * (3K) readcap = H(writecap)[:K] + H(pubkey)
+ * (minimum 3K) readcap = H(writecap)[:K] + H(pubkey)
  * (3K) traversalcap: H(readcap)[:K] + H(pubkey)
  * verifycap = H(pubkey)
  * storage-index = truncated verifycap