Upvote:2
Pope Benedict XVI may have resigned as of February 28,2013 but he would be able to publish works with the permission of Pope Francis and providing the works in question would not be a conflict of interest with the pontificate of Pope Francis and his successors. Will he publish anything? Probably not. One thing is absolute: Pope Emeritus Benedict XVI can never publish any official documents whatsoever. Pope Francis acknowledged the efforts of his predecessor when he published his first encyclical Lumen Fidei of July 5, 2013. https://zenit.org/articles/official-summary-of-lumen-fidei/
Pope Emeritus Benedict XVI is not going into solitude to hide as some believe, but is retiring from the world, in order to lead a life of prayer and contemplation.
The writings of a deceased pontiff (retired pontiff) are not to be destroyed unless explicitly mentioned in the last will and testament of the defunct pontiff. You can read about this in chapter V (part I) of Universi Dominici Gregis of Pope John Paul II. http://w2.vatican.va/content/john-paul-ii/en/apost_constitutions/documents/hf_jp-ii_apc_22021996_universi-dominici-gregis.html
Personal writings and documents of a deceased pope are to be stored in the Vatican Secret Archives and are not to be open until 75 years after the death of that pope. You can see where the works of Pope John Paul II are stored in his video. https://www.youtube.com/watch?v=urLxLj_UU8w
Upvote:7
The ex-pope can't publish anything as a pope - his seal is destroyed and he has no longer the right to use his papal name in this way. Documents he didn't manage to publish won't be destroyed, but are open to use by his successor, as the site linked in Svidgen's comment states.
No one can forbid the ex-pope to publish books under his civic name, though it's a tradition for an ex-pope to refrain from anything that might have "political" consequences. I personally (with no qualification, I just guess) expect Joseph Ratzinger to publish some of his yet unpublished works (otherwise, someone would publish them posthumously) - I guess he has enough unpublished (or unfinished) materials from his academic times.