GENEVA, Switzerland — A group of investors led by Swiss watchmaker Franck Muller is preparing to make an offer to buy a stake in Italian fashion house Roberto Cavalli, people familiar with the matter said.

The group may offer to buy between 60 percent and 70 percent of the Florence, Italy-based company for more than 300 million euros ($408 million), said the people, who asked not to be named as the matter is private.

Spokespeople for Geneva-based Genthod Global Wealth Management, the family office of Franck Muller Group, did not immediately respond to telephone and e-mail requests seeking comment. A spokeswoman for Cavalli declined to comment.

Muller has a license to make watches for Cavalli. He also sells timepieces such as the Conquistador under the Franck Muller brand, which carries the slogan “Master of Complications.”

The fashion and luxury-goods industry is consolidating as large groups such as LVMH Moet Hennessy Louis Vuitton SA seek new sources of revenue and small companies turn to investors to help fund growth. Gianni Versace SpA in February agreed to sell a 20 percent stake to Blackstone Group LP for 210 million euros, while cashmere clothier Loro Piana SpA in July sold 80 percent to LVMH for 2 billion euros.

Cavalli’s earnings before interest, taxes, depreciation and amortization were 22.4 million euros in 2013 on revenue of 201 million euros.

By Andrew Roberts, Kiel Porter; Editors: Celeste Perri, Paul Jarvis