Comment by AdieuToLogic

For the purposes of this post, American Express is not germane and thus omitted.

To fully understand this press release, we have to start with "the five circles" diagram which shows the simplest form of the entities involved in credit card processing:

          /-----------------\
          | Payment Network |
          \-----------------/
          /                \
  /--------\             /-----------\
  | Issuer |             | Processor |
  \--------/             \-----------/
      |                       |
  /-------------\        /----------\
  | Card Holder |        | Merchant |
  \-------------/        \----------/

  An example of a Payment Network is Visa.

  Issuer and Processor are banks allowed to connect to the
  Payment Network directly.

  Card Holder is a person who has a credit card account
  provided by an Issuer.

  Merchant is a company which performs credit card
  transactions via their Processor.

Now, companies which are neither a bank nor sponsored by a bank cannot directly interact with a Payment Network. Visa, MasterCard, Discover, none of them. Those companies must use a Processor (more on this later).

Which is why Chase (or bank equivalent) must be the "new issuer of Apple Card", since only an Issuer can do so (as illustrated above).

An important concept to revisit is that only banks or companies sponsored by banks can connect to a Payment Network. Companies sponsored by banks in order to enable them to directly communicate on a Payment Network are typically other banks and often have to give up an ownership stake to their sponsor.

Which means there must exist another element in the "five circles" diagram to explain offerings such as Apple Pay, PayPal, Stripe, Venmo, etc.:

          /-----------------\
          | Payment Network |
          \-----------------/
          /                \
  /--------\             /-----------\
  | Issuer |             | Processor |
  \--------/             \-----------/
      |                       |
      |                    /-----\
      |                    | ISO |
      |                    \-----/
      |                       |
  /-------------\        /----------\
  | Card Holder |        | Merchant |
  \-------------/        \----------/

Here, "ISO" are the payment services such as the aforementioned Apple Pay, PayPal, Stripe, Venmo, and friends. Ultimately, though, it is a bank which is the Processor which powers them. And in the Processor space, Chase is the 800lb gorilla.