diff --git a/django/sp_sso/saml/forms.py b/django/sp_sso/saml/forms.py
index 9cf0224..d8ac38a 100644
--- a/django/sp_sso/saml/forms.py
+++ b/django/sp_sso/saml/forms.py
@@ -1,7 +1,7 @@
 from django.utils.translation import ugettext_lazy as _
 from django import forms
 from .utils import ldap_get_unites, ldap_get_etablissements, sso_attributes, \
-    sso_select_attributes, sso_tupled_attributes
+    sso_select_attributes, sso_tupled_attributes, sso_strict_readonly_attributes
 
 
 AFFILIATION_CHOICES = (
@@ -82,6 +82,9 @@ class RegistrationForm(forms.Form):
                                 backend_dict.get(simple_choice)),)
                 self.fields[field].widget.attrs['readonly'] = True
 
+            if field in sso_strict_readonly_attributes:
+                self.fields[field].widget.attrs['readonly'] = True
+
     nom = forms.CharField(max_length=100, label=_("Last name"))
     prenom = forms.CharField(max_length=100, label=_("First name"))
     email = forms.CharField(max_length=100, label=_("Email address"))
diff --git a/django/sp_sso/saml/utils.py b/django/sp_sso/saml/utils.py
index adcc20b..8854ff3 100644
--- a/django/sp_sso/saml/utils.py
+++ b/django/sp_sso/saml/utils.py
@@ -28,6 +28,8 @@ sso_tupled_attributes = {
     's_emp_corps': 'EMP_CORPS_CHOICES'
 }
 
+sso_strict_readonly_attributes = ['invite_unite']
+
 supann_host_role_attribute = 'supannRoleGenerique'
 supann_host_role_value = '{SUPANN}R10' # 'Responsable de mission'