"Harvard University's Marriott code 17885 is an academic institutional code. No FlyerTalk thread discusses Harvard verification incidents. University codes at Marriott receive the lowest enforcement treatment — hotel staff view academic institutional rates as similar to government rates in terms of legitimacy. Harvard's Cambridge MA presence means nearby Marriott properties (Marriott Boston Cambridge, Sheraton Commander) are familiar with Harvard employees. No verification incident documented."

"FlyerTalk community specifically notes the MMM code as "the go-to code for the Minneapolis/St. Paul area, described as extremely reliable at local Courtyard and Residence Inn properties, with a low risk rating." One user documented using an IBM rate for 14 years at 80-100+ nights annually and "never once being asked for an ID." Another stayed 500+ nights and was never asked. The 3M code is regionally well-known near 3M's Minnesota HQ."

"I used to China often for work and book directly. I’ve never been asked, if you have a sticker or they can see something with the company logo they assume you work there. I’ve only been asked in Korea and was a hot mess until a manager stepped in."