This is a scam, they claim to be various companies or departments of companies. Often going by "Investigative Check Services" or just answering as "arbitration," and they often have personal information including your social security number. The FBI and Better Business Bureau has posted about them. Do not, under any circumstances, deal with these people or give any information to them whatsoever. Even if they actually send a person to your home or place of employment, which according to the BBB they sometimes have the balls to do. They are a scam.