I just got a letter informing me I have been granted Marriott Gold status until Feb. 2017 "as a thank-you for your loyalty to Delta Privilege". They seem to have a broad definition of loyalty as I've stayed at a Delta Hotel just once in the past decade (back in 2007), and even that one was booked through Hotwire.

I was already Marriott Gold (until Feb 2016) due to my UA 1K status. (My loyalty to Marriott consists of one stay per year to use the free night from the Chase Visa)