While I'm sure a $99B loss would be devastating (after all, it would be more than double the combined insurance claims from 9/11, and close to 3x the combined claims from Hurricane Sandy), it's not at all clear to me how the materiality of that loss relates to Prudential's market cap, which is simply the floating value of all Prudential's outstanding shares.

I keep asking what the connection between market capitalization and significance of a particular loss, and, respectfully, you keep begging the question. "It could break the company". Ok, I mean, that sounds pretty plausible; it would be a world-historic loss. But what is it about Prudential's market cap that makes it one? Market value isn't book value.