Industry losses from Sandy would need to reach $50 billion in order to materially erode reinsurers' capital base, according to an analysis by Standard & Poor's.

While most current estimates fall near or below $20 billion, S&P says there is still much uncertainty as to what the final loss number will be. For one thing, the ratings agency says some market participants believe loss amounts could be 30-50 percent higher than estimated due to insurers' inability to enforce hurricane deductibles in some states.

Additionally, S&P says the wind-vs.-water debates so prevalent after Hurricane Katrina will re-emerge in Sandy's wake: “When major hurricanes hit the coast, it is difficult to determine whether wind or water caused the damage. This uncertainty as to whether private insurers, the government or the insured parties themselves are liable for the damage may result in costly and time-consuming litigation, as happened in 2005.”