STOCKHOLM—Ikea founder Ingvar Kamprad was forced to hand over billions of dollars to his sons following a bitter family feud, according to a new book on the global furniture giant.

The revelation appeared Thursday in business daily Dagens Industri which published excerpts from “Ikea on the Road to the Future”, co-authored by former Ikea executive Lennart Dahlgren, journalist Stellan Bjoerk and economist Karl von Schulzenheim.

The book, due to go on sale on September 27, contradicts the official version of the company’s history which holds that Kamprad signed over his empire to a complex network of overseas foundations in 1982.

The authors claim that Kamprad—who founded the company in 1943—held back a percentage of sales based on intellectual property rights for himself, triggering a long drawn-out battle with his three sons.

“We’re probably talking about 20 to 30 billion kronor (2.3 billion to 3.5 billion euros, $3.2 billion to $4.7 billion),” Stellan Bjoerk told Dagens Industri.

According to the book, Peter, Jonas and Mathias Kamprad later contested the decision, going as far as to hire lawyers in the US to fight their case that the money should stay in the family.

Kamprad “swung between fury and resignation,” wrote the authors, “attempting his usual habit of haggling” but he eventually gave up and lost much of his control over the company.

The authors contacted the family directly for their book but the family refused to comment on the feud. Instead their information was based on sources close to the company.

Ikea declined to comment when AFP sought a reaction to the book.

Ingvar Kamprad has lived in self-imposed tax exile in Switzerland since the 1970s but announced in June that he intended to return to Sweden.

The media-shy 87-year-old rarely appears in public alongside his sons.