For the global wealthy with money to hide, it has long been helpful to have a Swiss company at your side. One with a nameplate, a letter-box, and no employees.

But like banking secrecy over a decade ago, the Swiss shell-company industry is now facing a fundamental threat. In its fight against money-laundering, the government is now pursuing a draft law that would force firms to declare their true owners, and attorneys to speak up about suspect transactions.