diff --git a/swh/storage/postgresql/converters.py b/swh/storage/postgresql/converters.py
--- a/swh/storage/postgresql/converters.py
+++ b/swh/storage/postgresql/converters.py
@@ -214,8 +214,12 @@
         db_revision["committer_date"], db_revision["committer_date_offset_bytes"],
     )
 
-    assert author, "author is None"
-    assert committer, "committer is None"
+    assert (author is None) == (
+        db_revision["author_fullname"] is None
+    ), "author is unexpectedly None"
+    assert (committer is None) == (
+        db_revision["committer_fullname"] is None
+    ), "committer is unexpectedly None"
 
     parents = []
     if "parents" in db_revision:
@@ -234,9 +238,9 @@
 
     return Revision(
         id=db_revision["id"],
-        author=author,
+        author=author,  # type: ignore  # will pass in swh-model v5.1.0
         date=date,
-        committer=committer,
+        committer=committer,  # type: ignore  # will pass in swh-model v5.1.0
         committer_date=committer_date,
         type=RevisionType(db_revision["type"]),
         directory=db_revision["directory"],
diff --git a/swh/storage/sql/40-funcs.sql b/swh/storage/sql/40-funcs.sql
--- a/swh/storage/sql/40-funcs.sql
+++ b/swh/storage/sql/40-funcs.sql
@@ -562,7 +562,7 @@
         select committer_fullname as fullname, committer_name as name, committer_email as email from tmp_revision
     ) insert into person (fullname, name, email)
     select distinct on (fullname) fullname, name, email from t
-    where not exists (
+    where t.fullname is not null and not exists (
         select 1
         from person p
         where t.fullname = p.fullname
diff --git a/swh/storage/sql/60-indexes.sql b/swh/storage/sql/60-indexes.sql
--- a/swh/storage/sql/60-indexes.sql
+++ b/swh/storage/sql/60-indexes.sql
@@ -149,6 +149,14 @@
     validate constraint revision_date_offset_not_null;
   alter table revision
     validate constraint revision_committer_date_offset_not_null;
+
+  -- if the author is null, then the date must be null
+  alter table revision add constraint revision_author_date_check check ((date is null) or (author is not null)) not valid;
+  alter table revision validate constraint revision_author_date_check;
+
+  -- if the committer is null, then the committer_date must be null
+  alter table revision add constraint revision_committer_date_check check ((committer_date is null) or (committer is not null)) not valid;
+  alter table revision validate constraint revision_committer_date_check;
 \endif
 
 \if :dbflavor_default
diff --git a/swh/storage/sql/upgrades/183.sql b/swh/storage/sql/upgrades/183.sql
new file mode 100644
--- /dev/null
+++ b/swh/storage/sql/upgrades/183.sql
@@ -0,0 +1,42 @@
+-- SWH DB schema upgrade
+-- from_version: 182
+-- to_version: 183
+-- description: add support for NULL as revision.author or revision.committer
+
+insert into dbversion(version, release, description)
+    values(183, now(), 'Work In Progress');
+
+select swh_get_dbflavor() = 'read_replica' as dbflavor_read_replica \gset
+select swh_get_dbflavor() != 'read_replica' as dbflavor_does_deduplication \gset
+select swh_get_dbflavor() = 'mirror' as dbflavor_mirror \gset
+select swh_get_dbflavor() = 'default' as dbflavor_default \gset
+
+\if :dbflavor_does_deduplication
+  -- if the author is null, then the date must be null
+  alter table revision add constraint revision_author_date_check check ((date is null) or (author is not null)) not valid;
+  alter table revision validate constraint revision_author_date_check;
+
+  -- if the committer is null, then the committer_date must be null
+  alter table revision add constraint revision_committer_date_check check ((committer_date is null) or (committer is not null)) not valid;
+  alter table revision validate constraint revision_committer_date_check;
+\endif
+
+create or replace function swh_person_add_from_revision()
+    returns void
+    language plpgsql
+as $$
+begin
+    with t as (
+        select author_fullname as fullname, author_name as name, author_email as email from tmp_revision
+    union
+        select committer_fullname as fullname, committer_name as name, committer_email as email from tmp_revision
+    ) insert into person (fullname, name, email)
+    select distinct on (fullname) fullname, name, email from t
+    where t.fullname is not null and not exists (
+        select 1
+        from person p
+        where t.fullname = p.fullname
+    );
+    return;
+end
+$$;
diff --git a/swh/storage/tests/storage_tests.py b/swh/storage/tests/storage_tests.py
--- a/swh/storage/tests/storage_tests.py
+++ b/swh/storage/tests/storage_tests.py
@@ -1,9 +1,10 @@
-# Copyright (C) 2015-2021  The Software Heritage developers
+# Copyright (C) 2015-2022  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 from collections import defaultdict
+import contextlib
 import datetime
 from datetime import timedelta
 import inspect
@@ -55,6 +56,16 @@
 )
 
 
+@contextlib.contextmanager
+def disable_attrs_validator():
+    v = attr.validators.get_disabled()
+    try:
+        attr.validators.set_disabled(True)
+        yield
+    finally:
+        attr.validators.set_disabled(v)
+
+
 def transform_entries(
     storage: StorageInterface, dir_: Directory, *, prefix: bytes = b""
 ) -> Iterator[Dict[str, Any]]:
@@ -1308,6 +1319,52 @@
         end_missing = swh_storage.revision_missing(ids)
         assert set(end_missing) == set(ids) - {revision.id}
 
+    def test_revision_add_no_author_or_date(self, swh_storage, sample_data):
+        full_revision = sample_data.revision
+
+        with disable_attrs_validator():
+            # TODO: remove context manager when support for author=None
+            # lands in swh-model
+            revision = attr.evolve(full_revision, author=None, date=None)
+            revision = attr.evolve(revision, id=revision.compute_hash())
+            actual_result = swh_storage.revision_add([revision])
+        assert actual_result == {"revision:add": 1}
+
+        end_missing = swh_storage.revision_missing([revision.id])
+        assert list(end_missing) == []
+
+        assert list(swh_storage.journal_writer.journal.objects) == [
+            ("revision", revision)
+        ]
+
+        with disable_attrs_validator():
+            # TODO: remove context manager when support for author=None
+            # lands in swh-model
+            assert swh_storage.revision_get([revision.id]) == [revision]
+
+    def test_revision_add_no_committer_or_date(self, swh_storage, sample_data):
+        full_revision = sample_data.revision
+
+        with disable_attrs_validator():
+            # TODO: remove context manager when support for author=None
+            # lands in swh-model
+            revision = attr.evolve(full_revision, committer=None, committer_date=None)
+            revision = attr.evolve(revision, id=revision.compute_hash())
+            actual_result = swh_storage.revision_add([revision])
+        assert actual_result == {"revision:add": 1}
+
+        end_missing = swh_storage.revision_missing([revision.id])
+        assert list(end_missing) == []
+
+        assert list(swh_storage.journal_writer.journal.objects) == [
+            ("revision", revision)
+        ]
+
+        with disable_attrs_validator():
+            # TODO: remove context manager when support for author=None
+            # lands in swh-model
+            assert swh_storage.revision_get([revision.id]) == [revision]
+
     def test_extid_add_git(self, swh_storage, sample_data):
 
         gitids = [