What premium, if any, is being offered for the convertible bonds compared to their current market price?

Premium Assessment:

The brief you provided – an ad‑hoc announcement of Idorsia’s interim results on its 2025 and 2028 convertible‑bond repurchase – does not disclose the exact price at which Idorsia is offering to buy back the bonds nor the prevailing market price of those securities. Consequently, a definitive premium (e.g., “5 % above market”) cannot be calculated from the information given. In most Swiss corporate bond repurchase programs, issuers typically propose a modest premium (often in the 3‑10 % range) to incentivize holders to tender their positions, especially when the bonds are trading close to or above the conversion value.

Trading Implications:

Because the exact premium is unknown, traders should first obtain the exact offer price and compare it with the current bid/ask spreads for the 2025 and 2028 convertibles. If the offered price is only a modest premium (or even at parity) and the bonds are trading at a discount to the underlying equity conversion value, the repurchase may be attractive for holders seeking liquidity. Conversely, if the bonds are trading at a significant premium to the underlying stock’s price, holding the convertibles may still deliver upside. Until the precise terms are disclosed, a prudent approach is to monitor the bid‑ask spreads and any upcoming detailed offer documents, then decide whether to tender the bonds or keep them for potential further upside in Idorsia’s equity.