Enabling InterCompany gives an error in Odoo 9 community. The Enterprise SaaS version seems to work. See also https://www.odoo.com/nl_NL/forum/help-1/question/odoo-9-how-to-enable-inter-company-92992

ParseError: "Invalid view definition

Meer info over fout:
View inheritance may not use attribute 'string' as a selector.

Fout context:
Weergave`res.company.form.inherit`
[view_id: 742, xml_id: n/b, model: res.company, parent_id: 110]
None" while parsing /opt/odoo/.local/share/Odoo/addons/9.0/inter_company_rules/views/inter_company_so_po_view.xml:5, near
<record model="ir.ui.view" id="view_company_inter_change_inherit_form">
            <field name="name">res.company.form.inherit</field>
            <field name="inherit_id" ref="base.view_company_form"/>
            <field name="model">res.company</field>
            <field name="arch" type="xml">
                <xpath expr="//notebook/page[@string='Configuration']" position="inside">
                    <group string="Inter-Company Rules">
                        <field name="so_from_po" attrs="{'invisible': [('auto_generate_invoices', '=', True)]}"/>
                        <field name="po_from_so" attrs="{'invisible': [('auto_generate_invoices', '=', True)]}"/>
                        <field name="warehouse_id" attrs="{'required': [('po_from_so', '=', True)], 'invisible': [('po_from_so', '=', False)]}" domain="[('company_id', '=', active_id)]"/>
                        <field name="auto_validation" attrs="{'invisible': [('auto_generate_invoices', '=', True)]}"/>
                        <field name="auto_generate_invoices" attrs="{'invisible': ['|', ('so_from_po', '=', True), ('po_from_so', '=', True)]}"/>
                        <field name="intercompany_user_id" colspan="2" attrs="{'required': ['|','|',('so_from_po', '=', True), ('po_from_so', '=', True), ('auto_generate_invoices', '=', True)]}"/>
                    </group>
                </xpath>
            </field>
        </record>