Philipp Hildebrand resigned on Monday as chairman of the Swiss National Bank, after details of email exchanges suggested that he had played a more active role in his wife’s controversial currency trades.
Last week Mr Hildebrand denied any wrongdoing over his wife’s purchase of $500,000, just weeks before the SNB imposed a ceiling on the appreciating Swiss franc in August, sending the currency down sharply. She converted the dollars back into Swiss francs in October, netting a profit.

“I came to the conclusion that it’s not possible for me to deliver a definite proof that my wife requested the currency transaction without my knowledge,” Mr Hildebrand said at a briefing. “Unfortunately, mistakes were made around this transaction.”
Mr Hildebrand said last week that the currency transaction stemmed from the sale of a family ski chalet in early 2011. He maintained he had been unaware of his wife’s currency dealings and reported them to the SNB’s chief lawyer the day after being informed.
“I failed my husband in not considering the perception of a ‘conflict of interest’ created by my purchase of dollars,” Mrs Hildebrand, who met her husband while the two worked at a New York hedge fund, said in a statement.

But in a “Contact Report” dated August 15 and released by the SNB during the briefing, Felix Scheuber, Mr Hildebrand’s banker at Bank Sarasin, wrote that he and the SNB head had discussed “increasing his USD-exposure but he would leave it up to his wife Kashya to so decide”. He also summarised that instruction to the Hildebrands in a subsequent email.
In an August 16 note to Mr Scheuber, Mr Hildebrand wrote: “I am surprised [by the] reference to a dollar transaction in your email. We never discussed any dollar purchases yesterday.” In a reply, Mr Scheuber countered that “I also remember your saying in our yesterday’s conversation that if Kashya wants to increase the USD exposure then it is fine with you”.
The Swiss government said it “respected” Mr Hildebrand’s decision and “regretted” the developments that had led him to step down.

Mr Hildebrand implied he had been a victim of a political campaign orchestrated by the ultranationalist Swiss People’s party and its leader, Christoph Blocher. The party is opposed to the SNB’s currency policy.
Mr Hildebrand suggested the issue of credibility and recent intrusion into his family’s private life had been his prime considerations. “I am sad to take this step,” he said. “I loved this job, I fought like a lion for it.”
Mr Hildebrand will also step down from his other international regulatory jobs such as the deputy chairmanship of the Financial Stability Board, and will be succeeded initially by Thomas Jordan, SNB deputy chairman. Mr Jordan is also regarded as a likely permanent replacement.
On Saturday, the SNB’s supervisory body ordered executives to report transactions of more than SFr20,000 and open their bank details to outside scrutiny.
The Swiss franc rose swiftly to a four-month high on Monday after the news. It later fell back as analysts said the resignation of Mr Hildebrand was unlikely to affect the Swiss National Bank’s commitment to weaken the franc.

Additional reporting by Alice Ross in London