Corporate oil booms in low-tax Switzerland | Reuters

Over the past six months companies including offshore drilling contractors Noble Corp and Transocean, energy-focused engineering group Foster Wheeler and oilfield services company Weatherfield International have all announced plans to shift domicile to Switzerland.

"Switzerland has a stable and developed tax regime and a network of tax treaties with most countries where we operate," Transocean Chief Executive Bob Long said in a statement in October, when it announced its move. "As a result, the redomestication will improve our ability to maintain a competitive worldwide effective corporate tax rate."