Have you ever had a Roman Catholic say things like, "well Anglican priests are not real priests, you don’t have real communion" or "your mass is not real and doesn't count?"
While many Christians in the Anglican tradition simply do not worry about it, we should have an answer. Anglicans are an exception in the Protestant Church that retained the historic and ancient three-fold Holy Orders of 1. Deacon, 2. Priest, 3. Bishop.
The Roman Catholic Communion did not know what to do with this situation for many years. They could not deny that Anglicans were ordained in apostolic succession. Eventually as the Roman communion was again more tolerated in England in the 19th Century the Vatican saw the need to delineate between Anglican and Roman Catholics.
And so a papal bull was published in 1896 by Pope Leo XIII declaring Anglican Holy Orders (and therefore all Anglican deacons, priests, and bishops), "null and void."
It was - frankly - hard for anyone outside of the Roman Catholics to take too seriously because the criteria outlined made the Roman Catholic Holy Orders themselves "null and void." I commend this article to you as an explanation from the North American Anglican