Originally Posted by James Luckard

Aside from the last one, those are all the legacy "Sheraton" hotels that have been Sheratons in name only for many years, but are actually in the Luxury Collection. It's a holdover from when the ITT Sheraton Luxury division was formed from the most elite Sheraton hotels back in the 1990s. Over the last few years, most of the others (Ankara, London Park Tower, Imperial Kuala Lumpur, Sofia, etc) have been renamed to remove the Sheraton name or repositioned as legit Sheratons. I'm sure these last few will be renamed soon too, I suspect it's to do with waiting for contracts to run out, etc.