According to market sources, de Boni will become president and chief operating officer of Prada USA effective July 1, filling a post that has been vacant for more than two years as the fast-growing Italian luxury group decides whether to launch an initial public offering this year.
It is understood de Boni submitted his resignation at Valentino on Wednesday.
At Prada, he will report to Brian Blake, Prada Group's chief operating officer in Milan.
A popular and charismatic executive, de Boni, an Italian national, has spent most of his career in the United States, working since 1989 for brands controlled by Italy's Marzotto family, including Hugo Boss. Last fall, European private equity firm Permira bought Valentino Fashion Group, which also includes Hugo Boss, for $3.55 billion.
De Boni has been a rising star at the Roman fashion house. In January 2007, he was named Valentino SpA's worldwide president of sales, marketing and retail, in addition to his role as president and chief executive of Valentino USA.
Sources suggested he has recently been jockeying for turf with Stefano Sassi, VFG's ceo and chairman of Valentino. But in an interview last year, Sassi sang his praises, saying: "De Boni is a fighter, a team worker and has worked very well in the U.S....He manages his business in a way that allows us to consider him an entrepreneur."
Among de Boni's accomplishments at Valentino was building sales in America from $24 million in 2002 up to $67 million in 2006.
The U.S. accounts for 25 percent of the business. Valentino's 2007 consolidated sales were 261 million euros, or $357.8 million at average exchange. In the first quarter of this year, the brand did particularly well in the U.S., where, stripping out the effects of currency fluctuations, sales gained 38 percent to 15 million euros, or $22.5 million.
A spokesman for Prada Group confirmed de Boni's appointment late Wednesday. De Boni and Valentino officials could not immediately be reached for comment.