diff --git a/src/uncategorized/BackwardsCompatibility.tw b/src/uncategorized/BackwardsCompatibility.tw
index a677cece8a7ea6d0d84efa2fc6954dc82af993d4..4957ab1e9ae70cebf1104e1b9f3c29a41ec8b705 100644
--- a/src/uncategorized/BackwardsCompatibility.tw
+++ b/src/uncategorized/BackwardsCompatibility.tw
@@ -2155,6 +2155,16 @@ Setting missing global variables:
 	<<set $youngerOvaries = 0>>
 <</if>>
 
+<<if ndef $pregInventor>>
+	<<set $pregInventor = 0>>
+<</if>>
+<<if ndef $pregInventorID>>
+	<<set $pregInventorID = 0>>
+<</if>>
+<<if ndef $pregInventions>>
+	<<set $pregInventions = 0>>
+<</if>>
+
 /* Job Fulfillment Center */
 <<if ndef $JFCOrder>>
 	<<set $JFCOrder = 0>>