M. Orange

It says in the article.

Law enforcement use CSS to pinpoint the location of phones often with greater accuracy than other techniques such as cell site location information (CSLI) and without needing to involve the phone company at all. CSS can also log International Mobile Subscriber Identifiers (IMSI numbers) unique to each SIM card, or hardware serial numbers (IMEIs) of all of the mobile devices within a given area. Some CSS may have advanced features allowing law enforcement to intercept communications in some circumstances.

Looks like they aren’t using “IMSI catcher” because it only covers one of the uses of those devices.