"The AON Hyatt code delivers unusually deep discounts at certain European properties, notably Paris. Hyatt is known as more verification-active than Marriott: "Hyatt is notorious for checking for ID and being quite thorough." Park Hyatt properties explicitly state "Valid Company ID Required at Check-in." One verified traveler reported Park Hyatt Tokyo demanding proof or threatening rack rate conversion, taking 15 minutes of email-searching to satisfy. For AON specifically, no denied-rate incident was found, but Hyatt's general enforcement rate is estimated at 10-20% of stays."

"I use corporate codes all the time and never get asked. I shouldn’t be using them but, hey, it is what it is. The risk is you get that front desk agent (or even manager) who goes “I see your with the Coca-Cola rate, can I have your corporate Id please”? Has never happened to me yet but it is a risk. So book accordingly."

"I know that my former employer, a very large non US-based multinational company (I am not sure if US-based companies are more careful due to liability issues etc.), doesn't really care whether or not the person using its hotel corporate rates (worldwide agreements with 2 different large hotel chains) is an employee. In fact the company secretly hopes that others (non-staff) use its corporate rate. The name of the game is volume and the more the volume the better the company's leverage on the hotel. That is why it is usually the hotels who insist on asking for company IDs or business cards (which I suppose anyone can print ... though I am not suggesting that FTers should go this route)."