Since that time, Opus Libros has obtained a copy of the "Index," which they have shared with ODAN.

Opus Dei continues to deny that they have an official list of forbidden books:

"Father Guillaume Derville, spiritual director of Opus Dei, said that Opus Dei has a “database” containing thousands of reactions to books by members over the years, which can be consulted when people want guidance on particular titles. “There are books that without even dealing with religious themes are impregnated with an anti-Christian ideology,” Derville said. “Others reflect a deep consistency with the teachings of the gospel, others are immoral, others could be of great help for all types of readers, and so on.” This database is not, Derville said, an “official list,” and the judgments expressed in it are “by definition perfectible.” Derville stressed that it is not an “index of forbidden books.” The database also contains more formal reviews, along with reactions from professors and friends." from Opus Dei: An Objective Look Behind the Myths and Reality of the Most Controversial Force in the Catholic Church by John L. Allen, Jr., Doubleday, 2005.

This database, which Opus Dei insists is not "an official list", is called Guia Bibliografica 2003 (Bibliographic guide 2003). Opus Libros has a detailed explanation of the Bibliographic Guide in Spanish at their website
[Guia Bibliografica]. The Guide consists of book reviews by Opus Dei members, biographical notes on some books and positive recommendations of others as Fr. Derville mentioned. However, there is also an actual list of over 60,000 books catalogued and rated according to the following criteria:

1. Books that can be read by all, even children; for example, Heidi, Marco, some stories of the Grimm Brothers, and all books written by members of Opus Dei.

2. Reading generally recommended, although it may require a little formation. In the libraries of the centers, the public, numeraries and associate members have access to books with the 1 and 2 ratings.

3. Books that can be read by those who have formation. The books may have inconvenient scenes or commentaries. Permission is needed by their spiritual director.

4. Books that can be read by those who have formation and have a necessity to read them. Permission is needed by their spiritual director.

5. Books that are not possible to be read, except with special permission from the advisory (in New York).

6. Prohibited reading. In order to read them permission is needed by the Prelate of Opus Dei (in Rome).

ODAN is focusing on this list because the other information and reviews are mostly written in Spanish. The list appears to be centralized because the books are listed in different languages; for example, the titles of books by Karl Marx are listed in French, Spanish and German; the books of John O'Hara are listed in English and Italian and the books of Edith Wharton are listed in English, French and Spanish.

There are 6,892 books with the highest rating of "6." Examples of authors who have some books with a "6" rating are: Woody Allen, Isabel Allende, Karen Armstrong, Margaret Atwood, Judy Blume, Roberto Bolano, Joseph Campbell, Gustav Flaubert, Allen Ginsberg, Mary Gordon, Gunter Grass, Andrew Greeley, Herman Hesse, Adolph Hitler, John Irving, James Joyce, Carl Jung, Eugene Kennedy, Jack Kerouac, Stephen King, Milan Kundera, Hans Kung, Harold Kushner, Henri Lefebvre, Doris Lessing, Sinclair Lewis, Richard P. MacBrien, Mary MacCarthy, Malinowski, Karl Marx, Somerset Maugham, Toni Morrison, Alice Munroe, Vladimir Nabokov, V.S. Naipaul, Pablo Neruda, Nietzcshe, Octavio Paz, Harold Pinter, Marcel Proust, Philip Roth, Bertrand Russell, John Updike, Gore Vidal, Voltaire, Alice Walker, Gary Wills and Tennessee Williams.

Examples of authors who have some books with a "5" rating are: W.S. Burroughs, John Cornwall, Marguerite Duras, William Faulkner, Nadine Gordimer, Eugene Kennedy, Jack Kerouac, Stephen King, Barbara Kingsolver, Doris Lessing, John O'Hara, A.J. Quinnell, Ayn Rand, Salman Rushdie and Kenneth Woodward.