sales_team_security/views/res_partner_view.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
<data>
    <record id="view_partner_form" model="ir.ui.view">
        <field name="name">Partner form (with sales team in contacts)</field>
        <field name="model">res.partner</field>
        <field name="inherit_id" ref="base.view_partner_form"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='child_ids']/form//field[@name='function']" position="before">
                <field name="section_id" invisible="1" groups="base.group_multi_salesteams"/>
            </xpath>
        </field>
    </record>
</data>
</openerp>