Good points all, Lothar. Mexico is in a different situation here from other WTO Members - per the FTA it is legally entitled to be either excluded or fully compensated from Day 1 (ie, without the 3 year grace period). And it would not need to use WTO procedures to exercise an FTA-based right. As you note, rights are not always exercised. But governments sometimes go to great lengths, eg by using DS systems, to acquire the right to suspend concessions. I don't think it is very common for existing/undisputed suspension-of-concession rights to go unutilized and even un-mentioned for years at a time, as is happening now. How broadly is it happening? Other commenters might know. The US solar safeguard case, where numerous WTO Members have been cozily sleeping on their rights for nearly 4 years, is a pretty significant instance and maybe not a unique one. If a key design element of the UR compromise on safeguards is, for whatever reason, simply falling out of use, I do think that is noteworthy.