"HP (alt) Marriott code 5105 is a secondary HP/HPE code, alongside the primary HPQ code and alt code 5444. HP's primary Marriott code HPQ is one of the most widely shared codes in FlyerTalk's publicly usable Marriott codes thread. The same risk profile applies to alt codes: Marriott's automated system has been documented to disable Mobile Key for high-risk codes, forcing front desk interaction. HP-heavy markets (Palo Alto, Houston TX) have heightened verification. No 5105-specific denial documented."

"I now always make it a matter of course to carry documents (business cards of my contacts, e-mails requesting my visit etc.) from my host company when I travel. This has always proven sufficient for the few times I've been challenged by the front desk clerk."

"My employer does not have a corporate rate but when I'm consulting for a company that does, I use theirs. I've only been challenged for identification once. In that one situation I explained the consulting arrangement, and the desk clerk accepted it without a badge or business card (neither of which I had anyway)."