"Morgan Stanley (alt) Marriott code 59009 is a secondary Morgan Stanley code alongside the primary MOS code. The same enforcement profile applies: financial sector Medium risk, with elevated scrutiny at NYC full-service Marriott properties (W Hotel, Westin, NY Marriott Marquis). hotelcorporatecodes.com rates finance codes as "⚠️ Sometimes." No 59009-specific denial documented; pattern mirrors the primary MOS code."

"I don't do mobile check-in if I'm wanting to upgrade. I check the app before I go in to see if any suites are available to book during the duration of my stay. If there is I just say "Would it be possible to get upgraded to an available suite with my platinum benefit?". Of course this is typically at the hotel that I stay in about once a month for 3 day at a time for work. The front desk pretty much knows me and know that I am fairly low maintenance."

"I have been asked to show some proof couple of times. I normally show my corp id but credit card with employers name on it has worked, too. As would probably just showing my laptop with employer e-mail account or whatever. My impression has been they are happy with just about anything that proves I'm working for the company whose rate I use and why wouldn't they."