TripIt informed subscribers to its TripItPro mileage-tracking service that they would no longer be able to keep a tallies of their United MileagePlus frequent flyer accounts starting December 11.

United Airlines thus joins the ranks of American Airlines, Delta Air Lines, and Southwest Airlines in refusing to let certain third-party mileage tracking sites from accessing members’ data. The airlines generally cite intellectual property security concerns for their choosing to bow out of most, if not all, of these third-party tracking sites.

TripIt’s email to TripIt Pro members follows:

 

Photo Credit: TripIt Pro's iphone app iTunes