"Conversion premium": The premium over an ordinary share's current market price at which the holder of the convertible security may convert it into ordinary shares. For example, say the current market price of the ordinary shares is Â£2, and the conversion price is Â£2. 50. The conversion premium = [Â£2. 50 - Â£2. 00 = Â£0. 50]/Â£2. 00 = 25%.