American Airlines is paying careful attention to the practice of “skiplagging” according to a recent travel agent communication.

In a January 26 memo , American said that it will begin monitoring booking practices that involve ticket booking practices such as churning, hidden city , inactive segments, marriage segments and origin and destination manipulation.

When these behaviors are identified, American warns of the possibility of unfavorable outcomes.

In a statement to TravelPulse, American said:

“We’ve always prohibited these types of booking practices, and have recently made some updates to our tools to more clearly display an alert when one of these practices may have occurred. We regularly make updates to our processes, and wanted to make sure we made all parties aware in case some account managers noticed an increase in the types of alerts they see on PNRs.”

The memo advises travel agents that “it is important that you familiarize yourself with these unfavorable practices as it will help prevent the issuance of future debit memos.”

It further states that the process of identifying these practices will be in an automated format with a phased rollout, starting with churning.

“We understand these unfavorable practices may occur due to confusion or misunderstanding of American’s policy,” the memo read. “We hope this advanced notification will be helpful with your future bookings.”