diff --git a/apis/paios/openapi.yaml b/apis/paios/openapi.yaml
index 68a4dd9e..d1b34dbb 100644
--- a/apis/paios/openapi.yaml
+++ b/apis/paios/openapi.yaml
@@ -1363,6 +1363,7 @@ components:
           $ref: '#/components/schemas/uuid4'
         user_id:
           type: string
+          format: uuid
           nullable: true
         expiration_dt:
           type: string
diff --git a/backend/models.py b/backend/models.py
index 251cbe4f..c7df9030 100644
--- a/backend/models.py
+++ b/backend/models.py
@@ -61,7 +61,7 @@ class Persona(SQLModelBase, table=True):
 class Share(SQLModelBase, table=True):
     id: str = Field(primary_key=True)  # the short URL tag, eg abcd-efgh-ijkl
     resource_id: str = Field(foreign_key="resource.id")  # the bot ID
-    user_id: str | None = Field(default=None)  # the user granted access (optional)
+    user_id: str | None = Field(foreign_key="user.id")  # the user granted access (optional)
     expiration_dt: datetime | None = Field(default=None)  # the link expiration date/time (optional)
     is_revoked: bool = Field()
 
diff --git a/backend/schemas.py b/backend/schemas.py
index fce66742..65217001 100644
--- a/backend/schemas.py
+++ b/backend/schemas.py
@@ -70,12 +70,10 @@ class ShareBaseSchema(BaseModel):
     expiration_dt: Optional[datetime] = None
     is_revoked: Optional[bool] = False
 
-    @field_serializer('user_id')
+    @field_serializer('user_id', when_used='unless-none')
     def serialize_user_id(self, user_id: str, _info):
         if user_id:
             return user_id
-        else:
-            return ""
 
     @field_serializer('expiration_dt', when_used='unless-none')
     def serialize_expiration_dt(self, dt: datetime, _info):
diff --git a/frontend/src/shares.tsx b/frontend/src/shares.tsx
index 9a656437..7bf560c2 100644
--- a/frontend/src/shares.tsx
+++ b/frontend/src/shares.tsx
@@ -11,6 +11,9 @@ const shareFilters = [
     <ReferenceInput source="resource_id" label="Resource" reference="resources">
         <SelectInput optionText="name" />
     </ReferenceInput>,
+    <ReferenceInput source="user_id" label="User" reference="users">
+        <SelectInput optionText="email" />
+    </ReferenceInput>,
 ];
 
 export const ShareList = () => (
@@ -20,6 +23,9 @@ export const ShareList = () => (
             <ReferenceField source="resource_id" reference="resources" link="show">
                 <TextField source="name" />
             </ReferenceField>
+            <ReferenceField source="user_id" reference="users" link="show">
+                <TextField source="email" />
+            </ReferenceField>
             <BooleanField source="is_revoked" />
         </Datagrid>
     </List>
@@ -32,6 +38,9 @@ export const ShareShow = () => (
             <ReferenceField source="resource_id" reference="resources" link="show">
                 <TextField source="name" />
             </ReferenceField>
+            <ReferenceField source="user_id" reference="users" link="show">
+                <TextField source="email" />
+            </ReferenceField>
             <DateField source="expiration_dt" label="Expires On" showTime locales="UTC" />
             <BooleanField source="is_revoked" />
         </SimpleShowLayout>
@@ -44,6 +53,9 @@ export const ShareEdit = () => (
             <ReferenceInput source="resource_id" label="Resource" reference="resources">
                 <SelectInput optionText="name" />
             </ReferenceInput>
+            <ReferenceInput source="user_id" label="User" reference="users">
+                <SelectInput optionText="email" />
+            </ReferenceInput>
             <DateTimeInput source="expiration_dt" label="Expires On (Optional)" />
             <BooleanInput source="is_revoked" />
         </SimpleForm>
@@ -56,6 +68,9 @@ export const ShareCreate = () => (
             <ReferenceInput source="resource_id" label="Resource" reference="resources">
                 <SelectInput optionText="name" />
             </ReferenceInput>
+            <ReferenceInput source="user_id" label="User" reference="users">
+                <SelectInput optionText="email" />
+            </ReferenceInput>
             <DateTimeInput source="expiration_dt" label="Expires On (Optional)" />
         </SimpleForm>
     </Create>
diff --git a/migrations/env.py b/migrations/env.py
index 499904f3..4c0a717a 100644
--- a/migrations/env.py
+++ b/migrations/env.py
@@ -57,6 +57,7 @@ def run_migrations_offline() -> None:
         literal_binds=True,
         dialect_opts={"paramstyle": "named"},
         include_schemas=True,
+        render_as_batch=True,
     )
 
     with context.begin_transaction():
@@ -81,6 +82,7 @@ def run_migrations_online() -> None:
             connection=connection,
             target_metadata=target_metadata,
             include_schemas=True,
+            render_as_batch=True,
         )
 
         with context.begin_transaction():
diff --git a/migrations/versions/4716615fdc5d_share_add_userid_foreignkey_constraint.py b/migrations/versions/4716615fdc5d_share_add_userid_foreignkey_constraint.py
new file mode 100644
index 00000000..a2596d17
--- /dev/null
+++ b/migrations/versions/4716615fdc5d_share_add_userid_foreignkey_constraint.py
@@ -0,0 +1,29 @@
+"""share convert user to FK
+
+Revision ID: 4716615fdc5d
+Revises: 187855982332
+Create Date: 2024-10-03 12:24:37.618156
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel
+
+
+# revision identifiers, used by Alembic.
+revision: str = '4716615fdc5d'
+down_revision: Union[str, None] = '187855982332'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    with op.batch_alter_table('share', schema=None) as batch_op:
+        batch_op.create_foreign_key('user_id', 'user', ['user_id'], ['id'])
+
+
+def downgrade() -> None:
+    with op.batch_alter_table('share', schema=None) as batch_op:
+        batch_op.drop_constraint(None, type_='foreignkey')