We are an insurance program manager (or "MGA" in insurance speak), and our insurance programs are back-stopped by Munich Re, one of the largest re-insurers in the world. We very purposefully didn't set the company up as traditional broker, because then we'd be reliant on a bunch of old-fashioned and off-line partners, which would undermines the experience we're trying to create for our clients.
Who insures you in case of a big claim that exceeds your equity?
A calamity like say the Exxon Valdez?
A great service but startups will pony up in good faith, but what happens when the chickens come home to roost?