Hamilton Insurance Group Ltd

Item 1A. Risk Factors

Item 1A. Risk Factors of our Annual Report on Form 10-K for the year ended December 31, 2025 contains a discussion of our known material risk factors. The disclosures below reflect material updates to certain of those risk factors and should be read in conjunction with the risk factor disclosures included in our Form 10-K. Except as described below, there hare have been no material changes to the risk factors previously disclosed.

Large claims or adverse market conditions could require us to liquidate investments at unfavorable times.

The occurrence of large insurance or reinsurance claims, catastrophic events or other unexpected liquidity demands could require us to liquidate investments at times when market conditions are unfavorable. Such forced asset sales may occur during periods of heightened volatility or reduced liquidity and could result in realized losses that would not otherwise have been incurred. In addition, forced sales may reduce our invested asset base, limit our ability to deploy capital into higher-yielding opportunities and impair our capacity to underwrite new business. These effects could materially adversely affect our business, financial condition and results of operations.

The Investment Agreement governing our investment in the TS Hamilton Fund, which replaced and superseded the prior commitment agreement as of April 1, 2026, includes certain conditions relating to our actions with respect to the fund, including notice periods, withdrawal limits and timing constraints. In particular, Hamilton Re is required to use reasonable best efforts to maintain an investment in the TS Hamilton Fund in an amount not less than the lesser of $1.8 billion or 60% of the Groups net tangible assets. While capital invested above the minimum commitment amount may generally be eligible for quarterly withdrawal, amounts invested at or below the minimum commitment amount are subject to extended notice periods and monthly withdrawal caps, which could delay our ability to access capital during periods of elevated claims activity or market stress. As a result, we may be unable to reallocate capital away from the TS Hamilton Fund to meet liquidity needs or pursue alternative investment opportunities, which could exacerbate the impact of adverse market conditions and materially adversely affect in Item 1A. Risk Factors of our business, financial condition and results of operations.

We have significant exposure to, and limited control over, the TS Hamilton Fund, which materially constrains our flexibility and could materially adversely affect our business, financial condition and results of operations.

A material portion of our investment portfolio is invested in the TS Hamilton Fund, which is managed by Two Sigma and, pursuant to the Investment Agreement, HamiltonAnnual Re is obligated to use reasonable best efforts to maintain an investment in the TS Hamilton Fund in an amount not less than the lesser of $1.8 billion or 60% of the Groups net tangible assets. We do not control the TS Hamiltport on Funds investment strategy or daytoday operations, have limited rights to withdraw capital, and cannot remove the Managing Member. Interests in the TS Hamilton Fund are illiquid, and our ability to withdraw capital is subject to contractual notice periods, withdrawal limits and timing constraints, which may restrict our access to capital. Under the Investment Agreement, our investment is subject to a twotier withdrawal structure that distinguishes between capital invested in excess of the minimum commitment amount and capital invested at or below such amount. Capital invested in excess of the minimum commitment amount may generally be withdrawn on a quarterly basis with advance notice, while capital invested at or below the minimum commitment amount is subject to extended notice periods and monthly withdrawal limitations that may require withdrawals to be effected over an extended period of time. Accordingly, a substantial portion of our assets invested in the TS Hamilton Fund may not be readily available to meet our liquidity needs, which could adversely affect our business, financial condition and results of operations.

The TS Hamilton Fund is not registered under the Investment Company Act of 1940, and thereorm 10-K fore we do not benefit from t the protections and requirements applicable to registered investment companies. In addition, the structural limitations of the TS Hamilton Fund, including its investment strategy and liquidity profile, limit our ability to reallocate capital, address adverse performance or market stress, or fund unexpected claim payments without forced sales of other assets, which could materially adversely affect our business, financial condition and results of operations.

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Our investment results depend heavily on Two Sigma and we are therefore exposed to their key personyear ended December 31, governance, operational and technology risks. These risks could materially adversely affect our business, financial condition and results of operations, and our contractual remedies are limited.

The TS Hamilton Fund performance depends on Two Sigmas ability to select and manage appropriate investments by combining multiple systematic, non-systematic and discretionary investment strategies. In recent years there have been a variety of management and governance challenges at Two Sigma and the management committee of Two Sigmas general partner has been unable to reach agreement on a number of topics including corporate governance and oversight matters, as well as the definition of roles, authorities, responsibilities and/or compensation for a range of C-level officers. These disagreements have affected Two Sigmas ability to retain and attract employees (including very senior employees) and could continue to impact the ability of Two Sigma employees to fully implement key research, engineering, or corporate business initiatives. As such disagreements continue, Two Sigmas ability to achieve the mandate of the TS Hamilton Fund could be impacted over time. In addition, regulatory investigations, litigation and other legal or regulatory matters involving Two Sigma or persons associated with it could divert management attention, adversely impact the stability of leadership teams, or affect employee morale and retention. If these developments persist or intensify, they could disrupt investment processes, alter strategic priorities, or otherwise negatively affect the TS Hamilton Funds performance. Regardless of management or governance developments, our ability to withdraw capital from the TS Hamilto2025, as updated by our subsequent Quarterly Report on Fund is subject to contractual limitations and governed by the withdrawal provisions set forth in the Investment Agreement and the related governing documents of the TS Hamilton Fund, including its Limited Liability Company Agreement, as may be amended from time to time.

The TS Hamilton Fund is exposed to operational risks from Two Sigma and its employees and service providers, including from potential non-compliance with policies and regulations, employee misconduct, negligence and fraud, each of which could result in material losses to torm 10-Q for the TS Hamilton Fund. In recent years, a number of investment managers and other financial institutions have suffered material losses due to, for example, the actions of traders executing unauthorized trades or other employee misconduct.

Two Sigmas highly complex and automated processes rely on advanced technology and large datasets, creating risks of coding errors, data inaccuracies, cybersecurity breaches, systems failures and process changes that may lead to unpredictable outcomes. Operational failures or employee misconduct, including unauthorized trading, could result in material losses, regulatory scrutiny and reputational harm. Any adverse or widely publicized developments at Two Sigma, whether related to governance matters, regulatory investigations, reputational issues or technology failures, could materially adversely affect the TS Hamilton Funds performance and, by extension, our business, financial condition and results of operations.

Conflicts of interest and regulatory scrutiny may adversely affect trade allocation, execution and performance.

Two Sigma and its affiliates manage multiple client and proprietary accounts with overlapping strategies, creating actual or perceived conflicts in trade allocation and execution. Decisions made for other clients, including deleveraging or liquidation, may negatively impact positions held by the TS Hamilton Fund. Under the Investment Agreement, Two Sigma retains substantial discretion in the management and allocation of the TS Hamilton Funds assets, including the ability to deviate from stated allocation targets and minimum expectations under certain limited circumstances. The Investment Agreement also recognizes that Two Sigmas obligations may be constrained by its fiduciary duties to other clients or by regulatory considerations, which could limit or delay investment opportunities or strategy execution for the TS Hamilton Fund. In addition, evolving regulation of alternative managers, derivatives, leverage and short selling may impose new restrictions, reporting obligations or emergency measures with little notice, which could impair liquidity and implementation of the TS Hamilton Funds investment strategy. Adverse developments involving Two Sigmas regulatory status or potential conflicts with other client mandates could limit its ability to implement investment decisions or execute trades for the TS Hamilton Fund, which may negatively affect the TS Hamilton Funds performance and, in turn, our business, financial condition and results of operations.

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quarter ended March 31, 2026.