diff --git a/.bumpversion.cfg b/.bumpversion.cfg
index 86c4ad0e4..9ae63ecc9 100644
--- a/.bumpversion.cfg
+++ b/.bumpversion.cfg
@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 6.6.1
+current_version = 6.6.2
 commit = True
 tag = False
 parse = (?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>[A-z0-9-]+)
diff --git a/api/graphql/schema.py b/api/graphql/schema.py
index 730c2d61a..2bb445ecf 100644
--- a/api/graphql/schema.py
+++ b/api/graphql/schema.py
@@ -484,7 +484,7 @@ class GraphQLSequencingGroup:
     technology: str
     platform: str
     meta: strawberry.scalars.JSON
-    external_ids: strawberry.scalars.JSON | None
+    external_ids: strawberry.scalars.JSON
 
     internal_id: strawberry.Private[int]
     sample_id: strawberry.Private[int]
@@ -498,7 +498,7 @@ def from_internal(internal: SequencingGroupInternal) -> 'GraphQLSequencingGroup'
             technology=internal.technology,
             platform=internal.platform,
             meta=internal.meta,
-            external_ids=internal.external_ids,
+            external_ids=internal.external_ids or {},
             # internal
             internal_id=internal.id,
             sample_id=internal.sample_id,
@@ -575,7 +575,7 @@ def from_internal(internal: AssayInternal) -> 'GraphQLAssay':
             id=internal.id,
             type=internal.type,
             meta=internal.meta,
-            external_ids=internal.external_ids,
+            external_ids=internal.external_ids or {},
             # internal
             sample_id=internal.sample_id,
         )
diff --git a/api/server.py b/api/server.py
index 4c3d1bcb8..3460ec285 100644
--- a/api/server.py
+++ b/api/server.py
@@ -20,7 +20,7 @@
 from api.settings import PROFILE_REQUESTS, SKIP_DATABASE_CONNECTION
 
 # This tag is automatically updated by bump2version
-_VERSION = '6.6.1'
+_VERSION = '6.6.2'
 
 logger = get_logger()
 
diff --git a/deploy/python/version.txt b/deploy/python/version.txt
index 09a7391e4..28179fc1f 100644
--- a/deploy/python/version.txt
+++ b/deploy/python/version.txt
@@ -1 +1 @@
-6.6.1
+6.6.2
diff --git a/models/models/assay.py b/models/models/assay.py
index 04658ad44..139d60327 100644
--- a/models/models/assay.py
+++ b/models/models/assay.py
@@ -12,7 +12,7 @@ class AssayInternal(SMBase):
     sample_id: int
     meta: dict[str, Any] | None
     type: str
-    external_ids: dict[str, str] | None = None
+    external_ids: dict[str, str] | None = {}
 
     def __repr__(self):
         return ', '.join(f'{k}={v}' for k, v in vars(self).items())
diff --git a/models/models/sequencing_group.py b/models/models/sequencing_group.py
index b1b493c8c..1ccd1a991 100644
--- a/models/models/sequencing_group.py
+++ b/models/models/sequencing_group.py
@@ -37,7 +37,7 @@ class SequencingGroupInternal(SMBase):
     platform: str | None = None
     meta: dict[str, str] | None = None
     sample_id: int | None = None
-    external_ids: dict[str, str] | None = None
+    external_ids: dict[str, str] | None = {}
     archived: bool | None = None
 
     project: int | None = None
diff --git a/setup.py b/setup.py
index 6050bba10..0b812b931 100644
--- a/setup.py
+++ b/setup.py
@@ -19,7 +19,7 @@
 setup(
     name=PKG,
     # This tag is automatically updated by bump2version
-    version='6.6.1',
+    version='6.6.2',
     description='Python API for interacting with the Sample API system',
     long_description=readme,
     long_description_content_type='text/markdown',
diff --git a/web/package.json b/web/package.json
index c9705d440..69ffc33f6 100644
--- a/web/package.json
+++ b/web/package.json
@@ -1,6 +1,6 @@
 {
     "name": "metamist",
-    "version": "6.6.1",
+    "version": "6.6.2",
     "private": true,
     "dependencies": {
         "@apollo/client": "^3.7.3",