Stone Ridge mutual cat bond and ILS fund assets near $6.5bn, highest since late 2018

Stone Ridge Asset Management, the New York based alternative risk premia focused investment manager, has reported assets under management across its mutual catastrophe bond, insurance-linked securities and reinsurance fund strategies nearing $6.5 billion, now at their highest levels since late 2018.

Stone Ridge Asset Management has now grown the insurance-linked securities (ILS) assets under management across its two main dedicated mutual cat bond and ILS fund strategies as well as its diversified alternatives fund by an impressive 24% over the last year of record.

As of January 31st 2026, the last official reporting date, the total AUM across the mutual 40’s Act ILS funds stood at just slightly under $6.3 billion, up from $5.09 billion a year earlier.

But assets growth has continued and as of March 31st we believe the total has reached around the $6.5 billion mark.

The last time Stone Ridge Asset Management had over $6.5 billion in its mutual cat bond and ILS fund strategies was in the fourth-quarter of 2018. By 2022, AUM had dipped to as low as $2.56 billion since when it has been on an upward trajectory recovering to the level we see today.

As of the January 31st 2026 reporting date, the Stone Ridge High Yield Reinsurance Risk Premium Fund which is the investment manager’s most catastrophe bond focused strategy, had grown to reach $4.14 billion of assets, up from $3.96 billion a quarter earlier.

However, by March 31st 2026 this more cat bond focused mutual fund strategy from Stone Ridge had reached $4.32 billion in AUM, setting another high for the size of this fund which has been growing steadily since a slight dip through 2017.

Meanwhile, the Stone Ridge Reinsurance Risk Premium Interval Fund, that invests across the spectrum of ILS and reinsurance-linked assets including sidecars and private quota shares, other collateralized reinsurance arrangements and to a lesser degree catastrophe bonds, reached $1.41 billion at January 31st 2026, remaining at its largest size in AUM terms since early 2022 and roughly flat with the prior quarter.

Data seen by Artemis suggests the Stone Ridge Interval fund has grown a little further, to reach about $1.5 billion at this time.

Finally, the Stone Ridge Diversified Alternatives Fund, a multi-strategy fund that began incorporating cat bond and ILS investments to its portfolio in 2023.

A quarter ago, the Diversified Alternatives Fund, had $783 million of cat bond and reinsurance investments, while a cross-investment into the Stone Ridge High Yield cat bond focused strategy was $78.84 million of that total.

As of January 31st 2026, total cat bond and ILS investments under this multi-strategy mutual fund had reached almost $790 million, while that cross-investment had shrunk back to $43.26 million. As a result, the direct holdings of cat bond and ILS instruments by this fund had grown by over $40 million in the quarter, to almost $746 million which made up 39% of the overall strategy’s assets.

All of the above took Stone Ridge Asset Management’s cat bond, ILS and reinsurance instrument assets under management across these mutual fund strategies to $6.3 billion at January 31st, but as we said this is now at or above $6.5 billion by this time, we believe.

With significant reinsurance-linked assets related to its private ILS fund strategies, managed accounts and its Longtail Re casualty focused structure, Stone Ridge remains a major force in the market and continues to build its stature as a long-term capital partner to the re/insurance industry.

At now assumed to be well over $10 billion, Stone Ridge remains one of the largest investment managers of ILS and reinsurance assets, in AUM terms, featured in Artemis’ directory of insurance-linked securities (ILS) fund managers.