Received data messages are delayed for further processing based on a bypass condition. Data messages that conform to the bypass condition are not delayed. Data messages that do not conform to the bypass condition are delayed by a delay. Data messages can be representative of orders in an electronic marketplace or trading system. The bypass condition can include indication of a post-only order. The bypass condition can further include indication of a volume that meets or exceeds a minimum volume. The delay can be calculated from a base delay and a variance that modifies the base delay. The variance can be randomly or pseudo-randomly selected and can conform to a maximum variance.