Originally Posted by
more4less
Yesterday I visited a UA/CO lounge and in the entrance there was a display mentioning the stickers.
If they even made displays for this matter, I would think they also informed other *A partners.
Especially at airports like Munich that have both Lufthansa and United departures, and where United and Lufthansa have joint revenue sharing (meaning it doesn't matter which metal you fly on or which ticket stock you have- the money is pooled).