"hotelcorporatecodes.com specifically categorises the Bayer/MLM code as "Rarely" for ID checks — the only entry rated below "Sometimes" in the pharma-sector Marriott codes. The MLM ticker does not correspond to an obvious company name, limiting its public notoriety. Pharma codes as a category are generally Medium, but Bayer's specific code consistently surfaces in the "low scrutiny" tier on aggregator sites, consistent with a large but relatively travel-light pharma footprint compared to consulting or finance."

"I also use AAA if the corporate is not available. In 10+ years of using AAA I had never been asked to show the card until last month in FL at two different properties. One was a HGI in Palm Beach Gardens and the other a CY in Stuart. Stayed at both since on AAA rate and wasn't asked."

"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."