diff --git a/migrations/versions/f2cb9f5ed836_.py b/migrations/versions/f2cb9f5ed836_.py
index b4536226b257c4d5e2726292abc50876ff2f1b6f..b3054a6c13fe732c6ad2f703563511b4b2261303 100644
--- a/migrations/versions/f2cb9f5ed836_.py
+++ b/migrations/versions/f2cb9f5ed836_.py
@@ -58,7 +58,6 @@ def upgrade():
                         length=120), nullable=True),
                     sa.PrimaryKeyConstraint('id'),
                     sa.UniqueConstraint('email'),
-                    sa.UniqueConstraint('uco'),
                     sa.UniqueConstraint('username')
                     )
     op.create_table('group',
diff --git a/portal/database/models.py b/portal/database/models.py
index 302d75890615b9db20fd0b27d81a0dcb2eb9b554..6d4cb15a47e8f791f8bbb785a19955e43ed3f5c6 100644
--- a/portal/database/models.py
+++ b/portal/database/models.py
@@ -56,7 +56,7 @@ class User(db.Model, EntityBase):
     __tablename__ = 'user'
     id = db.Column(db.String(length=36), default=lambda: str(
         uuid.uuid4()), primary_key=True)
-    uco = db.Column(db.Integer, unique=True)
+    uco = db.Column(db.Integer)
     email = db.Column(db.String(50), unique=True, nullable=False)
     username = db.Column(db.String(15), unique=True, nullable=False)
     name = db.Column(db.String(50))