"If you leave the company before 12 months. We will not provide you with an experience and reliveing letter. Your employment with us will be invalid and you will no longer be able to refer us to your future employers."<p>That seems to be a particularly bad warning sign.<p>Sane people might write:<p>"If you leave the company in your first 12 months, company policy is to confirm your employment (title, dates) but offer no recommendation, positive or negative, to future employers."