Hello Mario Molinos,

You can use below rule to allow employee to see their own chatter.

<record model="ir.rule" id="employee_allow_own_chatter">

    <field name="name">Rule to Allow Own chatter</field>

    <field name="model_id" ref="model_mail_message"/>

    <field name="global" eval="True"/>

    <field name="domain_force">[('author_id', '=', user.partner_id.id)]</field>

</record>

Hope it may help you!

Thank you!

Regards,

Email:      odoo@aktivsoftware.com  

Skype: kalpeshmaheshwari

I solved it by a Record Rule in the mail.message model.

['|',('res_id','=',user.employee_ids.id),('model','!=','hr.employee')]