diff --git a/networks.rkt b/networks.rkt
index 515f92d..27dc3af 100644
--- a/networks.rkt
+++ b/networks.rkt
@@ -132,7 +132,8 @@
                [tbn-interaction-graph (->* (tbn?) (#:zero-edges boolean?)
                                            graph?)]
                [pretty-print-tbn-interaction-graph (-> graph? graph?)]
-               [sbn-interaction-graph (-> sbn? graph?)])
+               [sbn-interaction-graph (->* (sbn?) (#:zero-edges boolean?)
+                                           graph?)])
  ;; Predicates
  (contract-out [variable? (-> any/c boolean?)]
                [state? (-> any/c boolean?)]
@@ -1777,7 +1778,7 @@
 ;;; the interaction graph.
 (define (sbn-interaction-graph sbn
                                #:zero-edges [zero-edges #t])
-  (update-graph (tbn-interaction-graph sbn)
+  (update-graph (tbn-interaction-graph sbn #:zero-edges zero-edges)
                 #:v-func (match-lambda
                            [(cons var _) var])))