Denial of Inventory

When orchestrated through large scale bots, denial of inventory it leads to a condition where the online merchant has ALL of their inventory in the “hold” state, effectively blocking legitimate customers from being able to shop for these inventory items. Denial of inventory attacks commonly target high value retail items (e.g., sneakers, mobile devices, airline tickets) as well as restaurant reservations, delivery time-slots, and parking spots. The goal of a denial of inventory attack can vary from profit to competitive to disruptive where the attack is used as a denial of service attack.

Airline industry seat spinning is a widespread problem where bots traverse the flight reservation workflow up to the point of paying for the ticket, thereby holding seats on flights. Airlines typically have between 5-20 minutes of hold period for the payment step. During this period “seat spinners” try to then sell those airline tickets for a small profit. If they are not successful in booking any profit, they let the hold period expire and seats are returned back to the inventory. But due to repeated attempts of seat spinning the time window in which seats are available for legitimate customers reduces significantly and, in some extreme cases, these customers find flights completely booked. Repeated seat spinning causes airlines to run half empty flights as legitimate customers are not able to book tickets on their online platform.