Where does the coupon actually come from? What funds it?

The coupon is funded by selling optionality, specifically by entering into derivative structures that allow ARKY to capture the gap between implied and realized volatility in the underlying stocks. ARK's innovation universe tends to have wide price ranges, and that characteristic is what makes the stocks attractive for this strategy. More dynamic price behavior translates to more premium available to convert into income. The coupon does not come from dividends, interest, or capital appreciation. It comes from the systematic harvesting of volatility premium embedded in option pricing.