diff --git a/design/sales.md b/design/sales.md
index 6aa70a4..67f7cd2 100644
--- a/design/sales.md
+++ b/design/sales.md
@@ -170,7 +170,7 @@ state is validated.
 ### Sort order
 
 Slots in the queue should be sorted in the following order:
-1. Seen flag
+1. Seen flag (`true` flag should be lower than `false`)
 2. Profit (descending)<sup>1</sup>
 3. Collateral required (ascending)
 4. Time before expiry (descending)