They call and pretend to be from another company, one that might want to purchase your services. They ask a lot of questions. Then they ask for your CEO. If he's not available, they want his direct line or his cell-phone number. They'll claim it's very important because their CEO wants to speak to your CEO urgently. When you ask for their call back number , they'll claim they don't have one. Or they'll give you a fax number in a different state to call.
They're liars...trying to sell you their company's hospitality services or marketing symposiums.