View / Wall Street may have found its party pooper

You don’t worry about bad ideas on Wall Street. Those burn themselves out quickly. You worry about good ideas because eventually someone will come along, execute them badly, and ruin the party for everyone.

Few ideas on Wall Street have been better than the reinvention of insurance from stodgy backwater to dealmakers’ playground. Insurance premiums collected today and paid out years from now are an irresistible pot of money: Warren Buffett’s insurance empire brought in some $90 billion of investable money in 2025. That’s more than the total amount raised over the previous five years by all private-equity firms, excluding the two largest, KKR and Blackstone. Every big investment firm has piled into insurance, turning the risk dial up and printing money for themselves while regulators and ratings agencies looked the other way.

I’ve been writing about the risks for a while. Insurers can miscalculate on underwriting and pay out more in claims than they took in. Or they can put policyholders’ money into risky things and lose it. Greg Lindberg (convicted of fraud) and 777 Partners’ Josh Wander (currently accused of fraud) weren’t systemically important enough to spoil the fun.

Mark Walter may be.

Walter was an early and aggressive convert to spinning policyholders’ cash into exotic investments, building a vast empire of insurers and asset managers linked through Guggenheim, where he serves as CEO. He is now selling assets quickly to unwind that dragon’s nest of interlocking loans and resolve a Justice Department investigation. He’ll probably come up with the cash. But a regulatory crackdown looks increasingly likely, either through a concerted push by states — Delaware is getting spicy in its review of another big Wall Street insurance deal — or through the federal government deciding this is a risk best not left to 50 state agencies.

Finance’s hottest party may have found its pooper.