diff --git a/bookwyrm/activitypub/verbs.py b/bookwyrm/activitypub/verbs.py
index 900c9a21..3686b3f3 100644
--- a/bookwyrm/activitypub/verbs.py
+++ b/bookwyrm/activitypub/verbs.py
@@ -1,5 +1,5 @@
 """ undo wrapper activity """
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from typing import List
 from django.apps import apps
 
@@ -192,6 +192,8 @@ class Announce(Verb):
     """ boosting a status """
 
     published: str
+    to: List[str] = field(default_factory=lambda: [])
+    cc: List[str] = field(default_factory=lambda: [])
     object: str
     type: str = "Announce"
 
diff --git a/bookwyrm/models/status.py b/bookwyrm/models/status.py
index aa330d61..8038e3ee 100644
--- a/bookwyrm/models/status.py
+++ b/bookwyrm/models/status.py
@@ -377,7 +377,7 @@ class Boost(ActivityMixin, Status):
         """ the user field is "actor" here instead of "attributedTo" """
         super().__init__(*args, **kwargs)
 
-        reserve_fields = ["user", "boosted_status", "published_date"]
+        reserve_fields = ["user", "boosted_status", "published_date", "privacy"]
         self.simple_fields = [f for f in self.simple_fields if f.name in reserve_fields]
         self.activity_fields = self.simple_fields
         self.many_to_many_fields = []