"HP's Marriott code HPQ is one of the most widely shared codes in FlyerTalk's publicly usable Marriott codes thread. Marriott's automated system has been documented to disable Mobile Key for high-risk codes being used for the first time, forcing front desk interaction. HP's deep discounts — noted as cheapest in China by one source — make it a higher-risk code. Hotels in HP-heavy markets (Palo Alto, Houston) are familiar with the verification process."

"I think the generic 'show corp id' designation means show the company business card. I think a lot of us don't have them or, if we do & we're not going to an office that we'd need to show them, leave them at home. I worked for some F500s that didn't require corp ids with shiny smiling faces on them & others that did; same with company credit cards. All, however, provided biz cards when working for them."

"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."