Mia Wang

The idea that the insurance float is a source of perpetual and low-cost capital ignores the fundamental incentives for caution in the sector.
If we see the float as free capital, the dominant incentive is to invest aggressively to maximize returns.
However, the payments associated with future claims turn this capital into an eventual liability, requiring prudent reserve management.
A Nash equilibrium forms around capital preservation, as the risk of being unable to honor claims, as Japanese insurers faced with natural disasters have shown, far exceeds the gains from aggressive investing.
Ignoring this gain asymmetry is a risky strategy, as a default would have systemic consequences.

Labeling insurance float as potential liability rather than free capital radically changes the incentives for the insurer. If the premium is a pure asset, the dominant incentive is to maximize investment returns without constraints, but the reality of liabilities imposes a different strategic response. In Japan, the FSA requires insurers to maintain adequate reserves to cover claims, turning the float into a real regulatory compliance cost. The Nash equilibrium for an insurer is not to maximize float returns but to minimize the risk of non-payment of claims, as during earthquakes that mobilize significant funds. It is less a constraint than a condition of existence.

The idea that the insurance float is a contingent liability does not intrinsically contradict its value as a low-cost capital source, but rather reveals a game of incentives. If the premiums collected are a liability, their effective management represents a dominant strategy for generating investment profits. An insurer's goal is to minimize the cost of capital; the float offers this advantage if claims risks are well managed. It is a Nash equilibrium where reserve prudence allows for optimizing the investment returns, as demonstrated by investment companies managing insurance portfolios.

Berkshire Hathaway's expansion to mega-cap status has indeed changed investment incentives for everyone. If we consider that size has limited its informational advantages, this implies a strategic shift: the company must now prioritize stability and diversification rather than explosive returns that were possible with more targeted investments in smaller entities. This realigns investors' expectations with a different risk/return profile, less accessible to small investors seeking quick gains.

The expansion of Berkshire Hathaway's market capitalization, if it indicates a scale change, does not automatically mean a reduction in its informational advantages or capital allocation flexibility.
If a company of this size maintains a 19.9% annual compounded return, the incentive is clear: it has found ways to continue generating value, often leveraging its strategic liquidity reserves.
For example, Berkshire's ability to deploy massive capital during the 2008 financial crisis demonstrated a flexibility that other giants lacked, challenging the idea of an inevitable constraint.

Talking about insurance float as a 'perpetual' source is fallacious; it is a dangerous oversimplification. Regulators do not see these funds as free capital but as contingent obligations requiring rigorous management. The SEC would never approve such a characterization because it ignores the reserves needed to cover claims, especially for American insurance companies. A company like AIG has shown how a poor calculation of the float can lead to a systemic crisis.