diff --git a/bookwyrm/activitypub/__init__.py b/bookwyrm/activitypub/__init__.py
index a7439722..9f46e12a 100644
--- a/bookwyrm/activitypub/__init__.py
+++ b/bookwyrm/activitypub/__init__.py
@@ -10,6 +10,7 @@ from .note import Note, GeneratedNote, Article, Comment, Review, Quotation
 from .note import Tombstone
 from .interaction import Boost, Like
 from .ordered_collection import OrderedCollection, OrderedCollectionPage
+from .ordered_collection import BookList
 from .person import Person, PublicKey
 from .response import ActivitypubResponse
 from .book import Edition, Work, Author
diff --git a/bookwyrm/activitypub/base_activity.py b/bookwyrm/activitypub/base_activity.py
index 7ef0920f..3ebf2fab 100644
--- a/bookwyrm/activitypub/base_activity.py
+++ b/bookwyrm/activitypub/base_activity.py
@@ -130,6 +130,7 @@ class ActivityObject:
     def serialize(self):
         ''' convert to dictionary with context attr '''
         data = self.__dict__
+        data = {k:v for (k, v) in data.items() if v is not None}
         data['@context'] = 'https://www.w3.org/ns/activitystreams'
         return data
 
diff --git a/bookwyrm/activitypub/ordered_collection.py b/bookwyrm/activitypub/ordered_collection.py
index 335723f4..94254644 100644
--- a/bookwyrm/activitypub/ordered_collection.py
+++ b/bookwyrm/activitypub/ordered_collection.py
@@ -12,13 +12,20 @@ class OrderedCollection(ActivityObject):
     first: str
     last: str = None
     name: str = None
-    summary: str = None
     owner: str = None
     to: List[str] = field(default_factory=lambda: [])
     cc: List[str] = field(default_factory=lambda: [])
     type: str = 'OrderedCollection'
 
 
+@dataclass(init=False)
+class BookList(OrderedCollection):
+    ''' structure of an ordered collection activity '''
+    summary: str = None
+    curation: str = 'closed'
+    type: str = 'List'
+
+
 @dataclass(init=False)
 class OrderedCollectionPage(ActivityObject):
     ''' structure of an ordered collection activity '''
diff --git a/bookwyrm/models/base_model.py b/bookwyrm/models/base_model.py
index 889eb5f4..b652ae9f 100644
--- a/bookwyrm/models/base_model.py
+++ b/bookwyrm/models/base_model.py
@@ -140,20 +140,7 @@ class ActivitypubMixin:
 
     def to_activity(self):
         ''' convert from a model to an activity '''
-        activity = {}
-        for field in self.activity_fields:
-            field.set_activity_from_field(activity, self)
-
-        if hasattr(self, 'serialize_reverse_fields'):
-            # for example, editions of a work
-            for model_field_name, activity_field_name, sort_field in \
-                    self.serialize_reverse_fields:
-                related_field = getattr(self, model_field_name)
-                activity[activity_field_name] = \
-                        unfurl_related_field(related_field, sort_field)
-
-        if not activity.get('id'):
-            activity['id'] = self.get_remote_id()
+        activity = generate_activity(self)
         return self.activity_serializer(**activity).serialize()
 
 
@@ -225,7 +212,7 @@ class OrderedCollectionPageMixin(ActivitypubMixin):
 
 
     def to_ordered_collection(self, queryset, \
-            remote_id=None, page=False, **kwargs):
+            remote_id=None, page=False, collection_only=False, **kwargs):
         ''' an ordered collection of whatevers '''
         if not queryset.ordered:
             raise RuntimeError('queryset must be ordered')
@@ -234,18 +221,24 @@ class OrderedCollectionPageMixin(ActivitypubMixin):
         if page:
             return to_ordered_collection_page(
                 queryset, remote_id, **kwargs)
-        name = self.name if hasattr(self, 'name') else None
-        owner = self.user.remote_id if hasattr(self, 'user') else ''
+
+        if collection_only or not hasattr(self, 'activity_serializer'):
+            serializer = activitypub.OrderedCollection
+            activity = {}
+        else:
+            serializer = self.activity_serializer
+            # a dict from the model fields
+            activity = generate_activity(self)
+        if remote_id:
+            activity['id'] = remote_id
 
         paginated = Paginator(queryset, PAGE_LENGTH)
-        return activitypub.OrderedCollection(
-            id=remote_id,
-            totalItems=paginated.count,
-            name=name,
-            owner=owner,
-            first='%s?page=1' % remote_id,
-            last='%s?page=%d' % (remote_id, paginated.num_pages)
-        ).serialize()
+        # add computed fields specific to orderd collections
+        activity['totalItems'] = paginated.count
+        activity['first'] = '%s?page=1' % remote_id
+        activity['last'] = '%s?page=%d' % (remote_id, paginated.num_pages)
+
+        return serializer(**activity).serialize()
 
 
 # pylint: disable=unused-argument
@@ -287,3 +280,22 @@ class OrderedCollectionMixin(OrderedCollectionPageMixin):
     def to_activity(self, **kwargs):
         ''' an ordered collection of the specified model queryset  '''
         return self.to_ordered_collection(self.collection_queryset, **kwargs)
+
+
+def generate_activity(obj):
+    ''' go through the fields on an object '''
+    activity = {}
+    for field in obj.activity_fields:
+        field.set_activity_from_field(activity, obj)
+
+    if hasattr(obj, 'serialize_reverse_fields'):
+        # for example, editions of a work
+        for model_field_name, activity_field_name, sort_field in \
+                obj.serialize_reverse_fields:
+            related_field = getattr(obj, model_field_name)
+            activity[activity_field_name] = \
+                    unfurl_related_field(related_field, sort_field)
+
+    if not activity.get('id'):
+        activity['id'] = obj.get_remote_id()
+    return activity
diff --git a/bookwyrm/models/fields.py b/bookwyrm/models/fields.py
index c6571ff4..bc10156b 100644
--- a/bookwyrm/models/fields.py
+++ b/bookwyrm/models/fields.py
@@ -213,7 +213,10 @@ class PrivacyField(ActivitypubFieldMixin, models.CharField):
             setattr(instance, self.name, 'followers')
 
     def set_activity_from_field(self, activity, instance):
-        mentions = [u.remote_id for u in instance.mention_users.all()]
+        # explicitly to anyone mentioned (statuses only)
+        mentions = []
+        if hasattr(instance, 'mention_users'):
+            mentions = [u.remote_id for u in instance.mention_users.all()]
         # this is a link to the followers list
         followers = instance.user.__class__._meta.get_field('followers')\
                 .field_to_activity(instance.user.followers)
diff --git a/bookwyrm/models/list.py b/bookwyrm/models/list.py
index 801a3f2a..b567929b 100644
--- a/bookwyrm/models/list.py
+++ b/bookwyrm/models/list.py
@@ -33,6 +33,7 @@ class List(OrderedCollectionMixin, BookWyrmModel):
         through='ListItem',
         through_fields=('book_list', 'book'),
     )
+    activity_serializer = activitypub.BookList
 
     def get_remote_id(self):
         ''' don't want the user to be in there in this case '''
diff --git a/bookwyrm/models/status.py b/bookwyrm/models/status.py
index dad65974..093dd773 100644
--- a/bookwyrm/models/status.py
+++ b/bookwyrm/models/status.py
@@ -94,6 +94,7 @@ class Status(OrderedCollectionPageMixin, BookWyrmModel):
         return self.to_ordered_collection(
             self.replies(self),
             remote_id='%s/replies' % self.remote_id,
+            collection_only=True,
             **kwargs
         )