In the past, he worked for various companies in Switzerland and the United States in the areas of finance, retail and marketing.

In July 2022, Silvio Denz and entrepreneur Peter Spuhler acquired the Hotel Florhof in Zurich.

After a successful closing of the public tender offer made by Silvio Denz, the shares of Lalique Group AG have been delisted from SIX Swiss Exchange on the 4th of September 2024.

[14] Denz accumulated the world's largest private collection of vintage perfume bottles designed by René Lalique,[15][16] comprising over 650 original pieces.

[17] In 2008 the company acquired the French crystal warehouse Lalique S.A. After being restructured, the group became profitable again, with branding focused on art, decorative items, interior design, jewelry, perfume and hospitality.

[18] Co-branding projects were developed between Lalique and other luxury brands (including Bentley, The Macallan and Steinway & Sons).

Collaborations were also signed with artists such as Zaha Hadid, Jean-Michel Jarre, Damien Hirst, and Elton John,[19] resulting in collections for the company.

[21] Denz also converted René Lalique's villa in Wingen-sur-Moder into a luxury hotel and restaurant, which opened in September 2015[22] and holds two Michelin stars.

In 1998, acting with the same partners, he bought the Clos d'Agon[25] estate on the Costa Brava, which is overseen by the oenologist Peter Sisseck (Dominio Pingus).

[35] In February 2014, Denz acquired Château Lafaurie-Peyraguey, one of the few Premiers Grands Crus Classés of 1855 and one of the oldest vineyards in Sauternes.

Working with local partners, he buys, renovates, and then resells traditional town houses in Mayfair, Knightsbridge and Kensington.

Today, he is the owner of the world's largest private collection of bottles by the celebrated French glass artist René Lalique.