diff --git a/intrastat_product/__openerp__.py b/intrastat_product/__openerp__.py
index 77209d7..917ca49 100644
--- a/intrastat_product/__openerp__.py
+++ b/intrastat_product/__openerp__.py
@@ -24,7 +24,7 @@
 
 {
     'name': 'Intrastat Product',
-    'version': '1.4',
+    'version': '8.0.1.4.0',
     'category': 'Intrastat',
     'license': 'AGPL-3',
     'summary': 'Base module for Intrastat Product',
diff --git a/intrastat_product/models/intrastat_product_declaration.py b/intrastat_product/models/intrastat_product_declaration.py
index 7631959..a6789a1 100644
--- a/intrastat_product/models/intrastat_product_declaration.py
+++ b/intrastat_product/models/intrastat_product_declaration.py
@@ -181,13 +181,13 @@ class IntrastatProductDeclaration(models.Model):
         compute='_check_validity',
         string='Valid')
 
-    @api.one
+    @api.model
     @api.constrains('year')
     def _check_year(self):
-        s = str(self.year)
-        if len(s) != 4 or s[0] != '2':
-            raise ValidationError(
-                _("Invalid Year !"))
+        for this in self:
+            s = str(this.year)
+            if len(s) != 4 or s[0] != '2':
+                raise ValidationError(_("Invalid Year !"))
 
     _sql_constraints = [
         ('date_uniq',
@@ -197,29 +197,32 @@ class IntrastatProductDeclaration(models.Model):
          "or change the revision number of this one."),
     ]
 
-    @api.one
+    @api.multi
     @api.depends('company_id')
     def _compute_company_country_code(self):
-        if self.company_id:
-            self.company_country_code = \
-                self.company_id.country_id.code.lower()
+        for this in self:
+            if this.company_id:
+                this.company_country_code = \
+                    this.company_id.country_id.code.lower()
 
-    @api.one
+    @api.multi
     @api.depends('year', 'month')
     def _compute_year_month(self):
-        if self.year and self.month:
-            self.year_month = '-'.join(
-                [str(self.year), format(self.month, '02')])
+        for this in self:
+            if this.year and this.month:
+                this.year_month = '-'.join(
+                    [str(this.year), format(this.month, '02')])
 
-    @api.one
+    @api.multi
     @api.depends('month')
     def _check_validity(self):
         """ TO DO: logic based upon computation lines """
-        self.valid = True
+        for this in self:
+            this.valid = True
 
-    @api.one
-    @api.returns('self', lambda value: value.id)
+    @api.multi
     def copy(self, default=None):
+        self.ensure_one()
         default = default or {}
         default['revision'] = self.revision + 1
         return super(IntrastatProductDeclaration, self).copy(default)
@@ -812,11 +815,12 @@ class IntrastatProductComputationLine(models.Model):
         'res.country', string='Country of Origin of the Product',
         help="Country of origin of the product i.e. product 'made in ____'")
 
-    @api.one
+    @api.multi
     @api.depends('transport_id')
     def _check_validity(self):
         """ TO DO: logic based upon fields """
-        self.valid = True
+        for this in self:
+            this.valid = True
 
     @api.onchange('product_id')
     def _onchange_product(self):
diff --git a/intrastat_product/models/intrastat_transaction.py b/intrastat_product/models/intrastat_transaction.py
index bf04d32..ea9002e 100644
--- a/intrastat_product/models/intrastat_transaction.py
+++ b/intrastat_product/models/intrastat_transaction.py
@@ -41,15 +41,16 @@ class IntrastatTransaction(models.Model):
         default=lambda self: self.env['res.company']._company_default_get(
             'intrastat.transaction'))
 
-    @api.one
+    @api.multi
     @api.depends('code', 'description')
     def _compute_display_name(self):
-        display_name = self.code
-        if self.description:
-            display_name += ' ' + self.description
-        self.display_name = len(display_name) > 55 \
-            and display_name[:55] + '...' \
-            or display_name
+        for this in self:
+            display_name = this.code
+            if this.description:
+                display_name += ' ' + this.description
+            this.display_name = len(display_name) > 55 \
+                and display_name[:55] + '...' \
+                or display_name
 
     _sql_constraints = [(
         'intrastat_transaction_code_unique',
diff --git a/intrastat_product/models/intrastat_transport_mode.py b/intrastat_product/models/intrastat_transport_mode.py
index 1850497..484c84d 100644
--- a/intrastat_product/models/intrastat_transport_mode.py
+++ b/intrastat_product/models/intrastat_transport_mode.py
@@ -38,10 +38,11 @@ class IntrastatTransportMode(models.Model):
     name = fields.Char(string='Name', required=True, translate=True)
     description = fields.Char(string='Description', translate=True)
 
-    @api.one
+    @api.multi
     @api.depends('name', 'code')
     def _display_name(self):
-        self.display_name = '%s. %s' % (self.code, self.name)
+        for this in self:
+            this.display_name = '%s. %s' % (this.code, this.name)
 
     _sql_constraints = [(
         'intrastat_transport_code_unique',
diff --git a/intrastat_product/models/res_company.py b/intrastat_product/models/res_company.py
index ccf15d2..2995486 100644
--- a/intrastat_product/models/res_company.py
+++ b/intrastat_product/models/res_company.py
@@ -78,14 +78,15 @@ class ResCompany(models.Model):
             ('standard', 'Standard'),
             ('extended', 'Extended')]
 
-    @api.one
+    @api.multi
     @api.depends('intrastat_arrivals', 'intrastat_dispatches')
     def _compute_intrastat(self):
-        if self.intrastat_arrivals == 'exempt' \
-                and self.intrastat_dispatches == 'exempt':
-            self.intrastat = 'exempt'
-        elif self.intrastat_arrivals == 'extended' \
-                or self.intrastat_dispatches == 'extended':
-            self.intrastat = 'extended'
-        else:
-            self.intrastat = 'standard'
+        for this in self:
+            if this.intrastat_arrivals == 'exempt' \
+                    and this.intrastat_dispatches == 'exempt':
+                this.intrastat = 'exempt'
+            elif this.intrastat_arrivals == 'extended' \
+                    or this.intrastat_dispatches == 'extended':
+                this.intrastat = 'extended'
+            else:
+                this.intrastat = 'standard'