diff --git a/requirements.txt b/requirements.txt
index 62da03b4d..31b128915 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,6 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
 Babel>=1.3
 argparse
-dib-utils
+dib-utils  # Apache-2.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 11b8a0b86..a5dc39cc5 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,3 +1,6 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
 hacking>=0.9.2,<0.10
 
 coverage>=3.6