April 14 (Bloomberg) -- Opus Dei, the Roman Catholic group portrayed as murderers in ``The Da Vinci Code,'' asked Sony Corp. to include a disclaimer in its upcoming film of the novel that would label the thriller as entirely fictional.

``Such a decision by Sony would be an expression of respect toward Jesus Christ, the history of the Church and the religious beliefs of viewers,'' Seizo Inahata of Opus Dei's Japan information office, wrote in an April 6 letter to Sony's Japanese shareholders, directors, employees and the Tokyo-based company.

Sony's adaptation of Dan Brown's 2003 novel, directed by Ron Howard and starring Tom Hanks, opens May 17 at the Cannes Film Festival in France. The tale of Opus Dei and the Vatican violently covering up Christianity's true origins has sold more than 40 million copies and sparked an outcry from Catholic groups that say the book distorts the religion.

``We haven't decided on a response to the letter and decline to comment on the issue at the moment,'' Sony spokesman Koji Kurata in Tokyo said. ``We received the letter from Opus Dei on April 6.''

Bloomberg News obtained a copy of the letter, in Spanish, from Opus Dei headquarters in Rome. Opus Dei, an organization of 84,000 laypeople and priests in some 60 countries, posted an unsigned version in Japanese on its Japan Web site.

The New York-based Catholic League has also called for Sony to add a disclaimer to the film, according to a March 21 news release from the group, which seeks to defend Catholics and the Church from discrimination.

`Capital Markets'

Opus Dei, in its letter to Sony, raises the possibility that the company's stock price could be hurt if Sony doesn't exhibit corporate values such as respect for peoples' beliefs. Corporations' intangible values ``consolidate their economic value in the capital markets because they guarantee stability,'' the letter says.

``Some media have written that Sony is weighing the possibility of including at the start of the film a disclaimer that would declare this a work of fiction and that any resemblance to reality is purely a coincidence,'' the letter says. It then endorses the idea.

``The novel mixes reality and fiction, and in the end, one doesn't know where the lines are between true deeds and invented deeds, so that the reader who knows little history can arrive at the wrong conclusions,'' the letter says.

Opus Dei's office in Japan didn't immediately respond to phone messages requesting additional comment on how the letter was distributed.

On April 7, a London court cleared Brown of allegations he plagiarized the plot from an earlier book. Michael Baigent and Richard Leigh, authors of the non-fiction ``The Holy Blood and the Holy Grail,'' sued Brown's publisher Random House Inc. for copyright infringement, claiming the author made millions from their theories that Jesus Christ married Mary Magdalene and fathered a child, spawning a royal dynasty.

To contact the reporters on this story: Vernon Silver in Rome at vtsilver@bloomberg.net; Daisuke Takato in Tokyo at dtakato@bloomberg.net.

Last Updated: April 14, 2006 08:57 EDT