Essentially, your ISOs could end up being worth anywhere from a vast fortune … to nothing at all. Either way, it is usually hard to value or sell exercised ISO shares until after your company has completed its IPO. And there’s never a guarantee an IPO will come soon, or indeed, ever. Your company may instead secure private funding to fuel its growth, or it may not grow to the point that warrants an IPO. Even once an IPO is in the works, it could be delayed or canceled if market conditions change. Given the uncertainty, we recommend including a healthy dose of contingency planning in your financial plans.