Massenet, regarded as the fashion visionary of the soon-to-be-merged business, was to become its executive chairman and oversee its editorial content, one of NAP’s main strengths.

In a statement Yoox said that Massenet would not be a member of the merged group’s board.

Industry insiders said the writing was on the wall as Massenet and Federico Marchetti, the head of YOOX who will lead the new company, had different personalities and were known for not getting on particularly well.

The two had already fallen out last year when initial merger talks collapsed, sources close to the two companies said.

“She probably tried her best but in the end, she decided it was best to leave,” said one person close to NAP, adding that knowing Massenet, she would make sure not to burn bridges with either Marchetti or the new company. It was not immediately clear whether other senior NAP staff were also going to resign.

Marchetti and Massenet were not available for comment.

Richemont, which owns jewellers Cartier and Van Cleef & Arpels, agreed in March to sell NAP to Yoox in an all-share deal that valued NAP at the time at around $1.5 billion. Richemont was awarded 50% of the combined company’s share capital as part of the deal.

Since then, an independent arbiter gave NAP a much higher valuation which minority shareholders such as Massenet could use to argue their stake was worth more than what was agreed with Yoox.

The news came as Yoox announced earlier on Wednesday the merger had received all required anti-trust clearances and it expected the deal to be finalized next month.

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