Pier Luigi Loro Piana was born in Milan in December 1951, the son of Franco Loro Piana, and took a degree in economics at Bocconi University. In the 1970s, from 1975 according to German Wikipedia, he and his elder brother Sergio took over the family wool company, founded by their great-uncle Pietro in 1924, and ran it for some four decades, alternating as chairman and chief executive every three years.
The brothers took the company further upmarket with ultrafine fibres and new fabrics. They focused on cashmere and extra-fine wools, and their research produced the Tasmanian fabric. In the 1980s they launched the first ready-to-wear collection and a luxury goods division. Loro Piana began working with vicuña in 1994, and in 1997 agreed with the Peruvian government and Andean communities to source the fibre only from live animals; in 2008 it helped finance Peru's first private vicuña reserve. The first Loro Piana shop opened in Milan in 1998. Much of the sporting side of the brand, he has said, came from clothes the brothers made for their own yachting, riding, skiing and golf, such as wool and cashmere with a waterproof, windproof membrane: "For research and development, I was the first victim."
In 2013 the brothers sold 80% of the company to LVMH for about $2.6 billion, and Sergio died that December. Pier Luigi stayed on as deputy chairman. The family sold LVMH a further 5% in 2017 and, at the end of 2025, a stake that took LVMH's holding from 85% to 94%. In September 2026 he spoke at the opening of Loro Piana's new knitwear plant at Ghemme.
A keen sailor since his teens, he raced the yacht My Song, which he lost in 2019, and now cruises the world on the 51-metre explorer Masquenada; Loro Piana has sponsored sailing events for more than twenty years, including the Giraglia regatta.
Casadi has not verified the exact size of his remaining stake (English Wikipedia estimates about 10% before the 2025 sale) or his exact date of birth.