Note: This tip is taken from the white paper Avoiding Attrition Penalties by Michael Hough.
This is no reason why any trade show organizer should have to pay attrition penalties of any kind. First, avoid the problem completely by never signing an attrition clause:
Move your busines to properties (and cities) that will not make this demand.
Take large, guaranteed blocks only at one or two headquarters hotels that are sure to sell out.
To fill the rest of the block, agree with a group of overflow hotels to use your "best efforts" to promote their properties. But offer no performance guarantee.
If you must sign an attrition clause, take these steps to minimize your risk:
Way under forecast the block at each property.
Base the penalties on lost profit, not lost revenues.
Get credit for all rooms your attendees generate and always include the right to audit.
Clearly enumerate to your attendees all the benefits of staying at a hotel within the official block.