Just another Puerto Rico international bank whose entire business model is based around not (yet) having to comply with CRS and FATCA.
Being based in Puerto Rico and marketing itself as a "US bank" is both technically true and misleading. Yes, Puerto Rico is a US territory but, no, it's not what people usually think of when they think US.
See also: Stern Bank, FV Bank, GK Bank, EuroPacific Bank.