diff --git a/bookwyrm/migrations/0044_auto_20210207_1924.py b/bookwyrm/migrations/0044_auto_20210207_1924.py
new file mode 100644
index 000000000..ec95f7e20
--- /dev/null
+++ b/bookwyrm/migrations/0044_auto_20210207_1924.py
@@ -0,0 +1,30 @@
+# Generated by Django 3.0.7 on 2021-02-07 19:24
+
+import bookwyrm.models.fields
+from django.conf import settings
+from django.db import migrations
+import django.db.models.deletion
+
+def set_user(app_registry, schema_editor):
+    db_alias = schema_editor.connection.alias
+    shelfbook = app_registry.get_model('bookwyrm', 'ShelfBook')
+    for item in shelfbook.objects.using(db_alias).filter(user__isnull=True):
+        item.user = item.shelf.user
+        item.save(broadcast=False)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('bookwyrm', '0043_auto_20210204_2223'),
+    ]
+
+    operations = [
+        migrations.RunPython(set_user),
+        migrations.AlterField(
+            model_name='shelfbook',
+            name='user',
+            field=bookwyrm.models.fields.ForeignKey(default=2, on_delete=django.db.models.deletion.PROTECT, to=settings.AUTH_USER_MODEL),
+            preserve_default=False,
+        ),
+    ]
diff --git a/bookwyrm/models/shelf.py b/bookwyrm/models/shelf.py
index 38e5913b2..921b8617c 100644
--- a/bookwyrm/models/shelf.py
+++ b/bookwyrm/models/shelf.py
@@ -55,12 +55,7 @@ class ShelfBook(CollectionItemMixin, BookWyrmModel):
     shelf = fields.ForeignKey(
         'Shelf', on_delete=models.PROTECT, activitypub_field='target')
     user = fields.ForeignKey(
-        'User',
-        blank=True,
-        null=True,
-        on_delete=models.PROTECT,
-        activitypub_field='actor'
-    )
+        'User', on_delete=models.PROTECT, activitypub_field='actor')
 
     activity_serializer = activitypub.AddBook
     object_field = 'book'
diff --git a/bookwyrm/tests/views/test_shelf.py b/bookwyrm/tests/views/test_shelf.py
index 65f7ade52..4fa63689a 100644
--- a/bookwyrm/tests/views/test_shelf.py
+++ b/bookwyrm/tests/views/test_shelf.py
@@ -25,11 +25,12 @@ class ShelfViews(TestCase):
             remote_id='https://example.com/book/1',
             parent_work=self.work
         )
-        self.shelf = models.Shelf.objects.create(
-            name='Test Shelf',
-            identifier='test-shelf',
-            user=self.local_user
-        )
+        with patch('bookwyrm.models.activitypub_mixin.broadcast_task.delay'):
+            self.shelf = models.Shelf.objects.create(
+                name='Test Shelf',
+                identifier='test-shelf',
+                user=self.local_user
+            )
         models.SiteSettings.objects.create()
 
 
@@ -96,7 +97,8 @@ class ShelfViews(TestCase):
                 'name': 'cool name'
             })
         request.user = self.local_user
-        view(request, request.user.username, shelf.identifier)
+        with patch('bookwyrm.models.activitypub_mixin.broadcast_task.delay'):
+            view(request, request.user.username, shelf.identifier)
         shelf.refresh_from_db()
 
         self.assertEqual(shelf.name, 'cool name')
@@ -116,7 +118,8 @@ class ShelfViews(TestCase):
                 'name': 'cool name'
             })
         request.user = self.local_user
-        view(request, request.user.username, shelf.identifier)
+        with patch('bookwyrm.models.activitypub_mixin.broadcast_task.delay'):
+            view(request, request.user.username, shelf.identifier)
 
         self.assertEqual(shelf.name, 'To Read')
 
@@ -128,7 +131,8 @@ class ShelfViews(TestCase):
             'shelf': self.shelf.identifier
         })
         request.user = self.local_user
-        views.shelve(request)
+        with patch('bookwyrm.models.activitypub_mixin.broadcast_task.delay'):
+            views.shelve(request)
         # make sure the book is on the shelf
         self.assertEqual(self.shelf.books.get(), self.book)
 
@@ -142,7 +146,8 @@ class ShelfViews(TestCase):
         })
         request.user = self.local_user
 
-        views.shelve(request)
+        with patch('bookwyrm.models.activitypub_mixin.broadcast_task.delay'):
+            views.shelve(request)
         # make sure the book is on the shelf
         self.assertEqual(shelf.books.get(), self.book)
 
@@ -156,7 +161,8 @@ class ShelfViews(TestCase):
         })
         request.user = self.local_user
 
-        views.shelve(request)
+        with patch('bookwyrm.models.activitypub_mixin.broadcast_task.delay'):
+            views.shelve(request)
         # make sure the book is on the shelf
         self.assertEqual(shelf.books.get(), self.book)
 
@@ -178,7 +184,12 @@ class ShelfViews(TestCase):
 
     def test_handle_unshelve(self, _):
         ''' remove a book from a shelf '''
-        self.shelf.books.add(self.book)
+        with patch('bookwyrm.models.activitypub_mixin.broadcast_task.delay'):
+            models.ShelfBook.objects.create(
+                book=self.book,
+                user=self.local_user,
+                shelf=self.shelf
+            )
         self.shelf.save()
         self.assertEqual(self.shelf.books.count(), 1)
         request = self.factory.post('', {