Swiss billionaires buy Merck Serono HQ for biotech campus ZURICH (Reuters) - Swiss billionaire Ernesto Bertarelli has bought back the Geneva headquarters of his former biotech firm Serono, hoping to establish a biotech research campus. After selling the family business to German drugmaker Merck KGaA for $13.3 billion in 2006, the Harvard Business School graduate went on to win the America's Cup sailing prize for the second time. He and his former beauty queen wife Kirsty cut a high profile among the Swiss jet-set. To buy back the site, Bertarelli formed a company called Campus Biotech with fellow Swiss billionaire Hansjoerg Wyss, who made part of his fortune by selling Synthes, a maker of artificial joints, to Johnson & Johnson in 2011 for over $21 billion. Since selling Serono, Bertarelli, Switzerland's sixth richest man, has founded investment fund Ares Life Sciences which has stakes in medtech, pharmaceutical and diagnostic imaging companies. Last year he bemoaned Merck's decision to move Merck Serono's HQ to the German city of Darmstadt, affecting 1,250 jobs, saying that a large part of Serono's history had been written in Geneva. Switzerland has a reputation as a hub for biotech research and is home to nearly 250 biotech companies, employing more than 19,000 people. The pharmaceutical industry accounts for 4 percent of economic output. Details of the transaction were not disclosed. Merck said the property will be handed over on June 28. The Technical University in Lausanne (EPFL) and Geneva University are closely involved in the project and will use part of the site as a research center. Under the project, the Wyss Foundation will give the EPFL 100 million Swiss francs ($103 million) to convert part of the site into a bio- and neuroengineering center known as the "Wyss Institute." The consortium hopes to attract start-up companies to the remainder of the site. Additional reporting by Ludwig Burger in Frankfurt; Editing by David Cowell