Ramped-up efforts by governments to clamp down on tax evasion have reverberated world-wide, from the Cayman Islands and Monaco to Hong Kong and Singapore.

The latest battle is playing out in Germany, where authorities are offering to buy information on secret Swiss bank accounts. The scenario was oddly familiar for His Serene Highness Prince Max of Liechtenstein, chief executive of LGT Group. He was in Hong Kong this week visiting clients of the private bank and wealth-management firm owned by the principality's royal family.