Goldman Sachs Research maintains a bullish on CHF over the medium-term.

"The shift in the SNB's intervention bias has been key in capping any haven-based gains for the Franc so far, but we think a reacceleration in domestic Swiss inflation should be enough to shift that bias back to a neutral setting and uncover those haven benefits. This is the main angle through which we will be watching the SNB's upcoming meeting on June 18," GS notes.

"This path to looser SNB FX management is central to our expectation for further CHF outperformance in the months ahead, but several important risks remain. First and foremost, EUR/CHF carry-to-vol is close to post-2015 highs, weakening risk-reward in outright downside positions. Second, we find evidence that gold's shifting correlation to risk is spilling over to the Franc and is likely to continue to be a source of idiosyncratic vol for the Franc via its terms of trade linkages," GS adds.