Having a finite maturity date is generally preferable over a perpetuity ("forever"). I explained above that the value of a perpetuity declines rapidly when interest rates rise (and interest rates will be rising in the near future). For example, the government of Austria recently issued a 100 year bond, which then fell nearly 50% in value as interest rates increased. A perpetuity is even worse than a 100 year bond.
With a finite maturity, you invest (let's say) $2 million, earn your yield for 5 years (let's say LIBOR + 7%) and then you get your $2 million back and you can decide then how to best re-invest your money at that time given the situation. There is a reinvestment risk here, where after 5 years you might not be able to find similarly attractive investments but unless you an insurance company or a pension fund trying to meet very specific long-term obligations you don't really need to worry about super long-term reinvestment risk. On the flip side, if you get your money back after 5 years you might be able to find an even better investment, and that kind of optionality is very valuable.
> earn your yield for 5 years (let's say LIBOR + 7%) and then you get your $2 million back and you can decide then how to best re-invest your money at that time given the situation
You have an 80% chance of getting your money back with BBs.
Also, I didn't read the specs on the Listerine contract, but I assume that if they raise the price of Listerine, then royalties scale with it. While in short term consumer staple prices are sticky, they scale with inflation over the long haul.
