Why would you even compare the two? Box is a public company. Dropbox is a startup. A late-stage startup for sure, but the fact that it is still funded by private money puts it in a completely different asset class.
It’s irrational to value a private company using public-company metrics. By those measures, nearly every single consumer tech startup has a valuation of zero and their investors should go kill themselves.
Tech company finance looks something like this: Startups start up with venture money and are expected to deliver explosive growth. Many fail, some survive and continue to grow. One day, when the companies have grown into stable mature cash-flowers, they reward their venture investors by going public.
Public market valuations should reasonably be lower than private company valuations. After all, public investors are just cashing out the private investors who already rode out the exponential growth. That’s why it’s called an exit.
The Dropbox Valuation Is Irrational –CB Insights