I was reading an old article (2007) of a guy in Arizona who was excommunicated for apostasy. His stake President wrote him a letter stating that:
Church disciplinary actions are considered confidential, unless the infraction is very public and/or affects a lot of people. So, an excommunication for apostasy needs to be widely published so that other people will know that the person is teaching false, misleading doctrines.
Other than this type of case, all disciplinary actions are confidential, and only the persons direct leaders are notified.