Hamilton Insurance Group, Ltd.

Previous wording

We harness multiple drivers to create shareholder value, including diverse underwriting operations supported by proprietary technology and a team of over 550 full-time employees, a strong balance sheet, and a unique investment management relationship with Two Sigma. We operate globally, with underwriting operations in Lloyd’s, Ireland, Bermuda, and the United States.

Current wording

We harness multiple drivers to create shareholder value, including diverse underwriting operations supported by proprietary technology and a team of over 600 full-time employees, a strong balance sheet, and a unique investment management relationship with Two Sigma. We operate globally, with underwriting operations in London, Dublin, Bermuda and across the United States.

Previous wording

•Hamilton Global Specialty focuses predominantly on commercial specialty and casualty insurance for medium to large-sized accounts and specialty reinsurance products written by Lloyd’s Syndicate 4000 and HIDAC. Syndicate 4000, a leading Lloyd’s syndicate, generates a significant portion of premium from the U.S. E&S market and has ranked among the most profitable and least volatile syndicates at Lloyd’s over the last 10 years.

Current wording

•Hamilton Global Specialty focuses predominantly on commercial specialty and casualty insurance for medium to large-sized accounts and specialty reinsurance products written by Lloyd’s Syndicate 4000 and Hamilton Insurance DAC ("HIDAC"). Syndicate 4000, a leading Lloyd’s syndicate, generates a significant portion of premium from the U.S. Excess & Surplus ("U.S. E&S") market and has ranked among the most profitable and least volatile syndicates at Lloyd’s over the last 10 years.

Previous wording

•Hamilton Select, our recently launched U.S. domestic E&S carrier, writes casualty insurance for small to mid-sized clients in the hard-to-place niche of the U.S. E&S market. We believe it presents meaningful and profitable growth opportunities in the near to long term, further expanding our footprint in the U.S. E&S market.

Current wording

•Hamilton Select, our U.S. domestic E&S carrier, writes casualty insurance for small to mid-sized clients in the hard-to-place niche of the U.S. E&S market. We believe it presents meaningful and profitable growth opportunities in the near-to-long term, further expanding our footprint in the U.S. E&S market.

Previous wording

One of our key strategic priorities is sustainable underwriting profitability on the business we write. Our data-driven and disciplined underwriting processes position us to intelligently price and structure our products and our business portfolio. We maintain trusted and long-standing relationships with our clients and brokers, who we believe will continue to provide us with increased access to attractive business.

Current wording

One of our key strategic priorities is sustainable underwriting profitability across the business we write. Our data-driven and disciplined underwriting processes position us to intelligently price and structure our products and our business portfolio. We maintain trusted and long-standing relationships with our clients and brokers, who we believe will continue to provide us with increased access to attractive business.

Previous wording

We see growth opportunities in both the insurance and reinsurance markets in which we operate and intend to pursue disciplined growth across our underwriting platforms. In recent years the E&S market has benefited from a strong rate environment and increased submissions as business has shifted into the non-admitted market from the admitted market. Non-admitted insurers are able to cover unique and hard-to-place risks because they have flexibility of rate and form and can accommodate the unique needs of insureds who are unable to obtain coverage from admitted carriers. We believe the access our three underwriting platforms have to U.S. E&S insurance business will allow us to build a robust and diversified book of business and achieve our profitable growth objectives throughout various market cycles.

Current wording

We see continued growth opportunities in both the insurance and reinsurance markets in which we operate and intend to pursue disciplined growth across our underwriting platforms. In recent years the E&S market has benefited from a strong rate environment and increased submissions as business has shifted into the non-admitted market from the admitted market. Non-admitted insurers are able to cover unique and hard-to-place risks because they have flexibility of rate and form and can accommodate the unique needs of insureds who are unable to obtain coverage from admitted carriers. We believe the access our three underwriting platforms have to U.S. E&S insurance business will allow us to build a robust and diversified book of business and achieve our profitable growth objectives throughout various market cycles.

Previous wording

Our strong, sustainable underwriting operations are complemented by our unique investment portfolio, which consists of the Two Sigma Hamilton Fund ("TS Hamilton Fund" or "TSHF"), and our investment grade fixed income portfolio, which is currently benefiting from strong interest rates. We plan to continue to optimize our investment portfolio through a balanced allocation of invested assets and maintain the flexibility to adjust this allocation as needed. We believe our strategy of disciplined underwriting growth, balanced with our investment platform, will drive our ability to create shareholder value.

Current wording

Our strong, sustainable underwriting operations are complemented by our unique investment portfolio, which consists of the Two Sigma Hamilton Fund, LLC ("TS Hamilton Fund" or "TSHF"), and our investment grade fixed income portfolio, which is currently benefiting from strong interest rates. We plan to continue to optimize our investment portfolio through a balanced allocation of invested assets and maintain the flexibility to adjust this allocation as needed. We believe our strategy of disciplined underwriting growth, balanced with our investment platform, will drive our ability to create shareholder value.

Previous wording

We have a unique and long-term investment management relationship with Two Sigma. Founded in 2001, Two Sigma is a premier investment manager with a strong track record, driven by a differentiated application of technology and data science. The TS Hamilton Fund is a dedicated fund-of-one managed by Two Sigma with exposures to certain Two Sigma macro and equity strategies and is designed to provide low-correlated absolute returns, primarily by combining multiple hedged and leveraged systematic investment strategies with proprietary risk management investment optimization and execution techniques. The TS Hamilton Fund invests in a broad set of financial instruments and is primarily focused on liquid strategies in global equity, FX markets, exchange-listed and over the counter options (and their underlying instruments) and other derivatives. This liquidity profile fits well with our business, while also providing the benefit of access to a dedicated fund-of-one.

Current wording

We have a unique and long-term investment management relationship with Two Sigma. Founded in 2001, Two Sigma is a premier investment manager with a strong track record, driven by a differentiated application of technology and data science. The TS Hamilton Fund is a dedicated fund-of-one managed by Two Sigma with exposures to certain Two Sigma equity and macro strategies and is designed to provide low-correlated absolute returns, primarily by combining multiple hedged and leveraged systematic and non-systematic investment strategies with proprietary risk management investment optimization and execution techniques. The TS Hamilton Fund invests in a broad set of financial instruments and is primarily focused on liquid strategies in global equity, FX markets, exchange-listed and over the counter options (and their underlying instruments) and other derivatives. This liquidity profile fits well with our business, while also providing the benefit of access to a dedicated fund-of-one.

Previous wording

Two Sigma has broad discretion to allocate invested assets to different opportunities. Its current investments include Two Sigma Futures Portfolio, LLC ("FTV"), Two Sigma Spectrum Portfolio, LLC ("STV") and Two Sigma Equity Spectrum Portfolio, LLC ("ESTV"). The TS Hamilton Fund’s trading and investment activities are not limited to these strategies and techniques and the TS Hamilton Fund is permitted to pursue any investment strategy and/or technique that Two Sigma determines in its sole discretion to be appropriate for the TS Hamilton Fund from time to time.

Current wording

Two Sigma has broad discretion to allocate invested assets to different opportunities. Its current investments include Two Sigma Spectrum Portfolio, LLC ("STV"), Two Sigma Equity Spectrum Portfolio, LLC ("ESTV"), Two Sigma Absolute Return Portfolio, LLC ("ATV"), Two Sigma Futures Portfolio, LLC ("FTV"), Two Sigma Horizon Portfolio, LLC ("HTV"), Two Sigma Navigator Portfolio, LLC ("NTV") and Two Sigma Kuiper Portfolio, LLC ("KTV"). The TS Hamilton Fund’s trading and investment activities are not limited to these strategies and techniques and the TS Hamilton Fund is permitted to pursue any investment strategy and/or technique that Two Sigma determines in its sole discretion to be appropriate for the TS Hamilton Fund from time to time.

Previous wording

Historically, inflation has not had a material effect on the Company’s consolidated results of operations. However, global economic inflation has recently increased and there is a risk that it will remain elevated for an extended period. Inflation is subject to many macroeconomic factors beyond our control, including global banking policy, political risks, and supply chain issues. An inflationary economy may result in higher losses and loss adjustment expenses, negatively impact the performance of our fixed income security investment portfolio, or increase our operating expenses, among other unfavorable effects. The ultimate effects of an inflationary or deflationary period are subject to high uncertainty and cannot be accurately estimated until the actual costs are known.

Current wording

Historically, inflation has not had a material effect on the Company’s consolidated results of operations. However, over the last several years, global economic inflation has increased, and there is a risk that it will remain elevated for an extended period. Inflation is subject to many macroeconomic factors beyond our control, including global banking policy, political risks and supply chain issues. An inflationary economy may result in higher losses and loss adjustment expenses, negatively impact the performance of our fixed income security investment portfolio, or increase our operating expenses, among other unfavorable effects. The ultimate effects of an inflationary or deflationary period are subject to high uncertainty and cannot be accurately estimated until the actual costs are known.

Previous wording

On December 27, 2023, the Bermuda Government enacted a 15% corporate income tax that will generally become effective for Bermuda domiciled entities on or after January 1, 2025. The legislation defers the effective date until January 1, 2030 for so long as the consolidated group operates in six or fewer jurisdictions, has less than €50 million in tangible assets and none of its Bermuda entities are subject to the Income Inclusion Rule in any other jurisdiction. The act is a response to the OECD Pillar 2 worldwide minimum tax that would otherwise require a top-up tax be paid on Bermuda-sourced income to non-Bermuda jurisdictions such that a 15% minimum effective tax rate is achieved for Hamilton Group’s Bermuda entities. Hamilton Group expects to be exempt from the worldwide minimum tax until January 1, 2030, pursuant to an exemption similar to that available in Bermuda. The act includes a provision referred to as the economic transition adjustment, which is intended to provide a fair and equitable transition into the tax regime, and, as a result, the Company recorded a deferred tax benefit of $35.1 million in the year ended December 31, 2023.

Current wording

On December 27, 2023, the Bermuda Government enacted a 15% corporate income tax that generally became effective for Bermuda domiciled entities on or after January 1, 2025. The legislation defers the effective date until January 1, 2030 for so long as the consolidated group operates in six or fewer jurisdictions, has less than €50 million in tangible assets and none of its Bermuda entities are subject to the Income Inclusion Rule in any other jurisdiction. The act is a response to the OECD Pillar 2 worldwide minimum tax that would otherwise require a top-up tax be paid on Bermuda-sourced income to non-Bermuda jurisdictions such that a 15% minimum effective tax rate ("ETR") is achieved for Hamilton Group’s Bermuda entities. Hamilton Group expects to be exempt from the worldwide minimum tax until January 1, 2030, pursuant to an exemption similar to that available in Bermuda. The act includes a provision referred to as the economic transition adjustment ("ETA"), which is intended to provide a fair and equitable transition into the tax regime. As of March 31, 2025, the Company holds a deferred tax asset of $35.4 million on its balance sheet related to the ETA.

Previous wording

Our critical accounting estimates include "Reserve for Losses and Loss Adjustment Expenses", "Premiums Written and Earned", "Ceded Reinsurance and Unpaid Losses and Loss Adjustment Expenses Recoverable", and "Fair Value of Investments" and are discussed in Management’s Discussion and Analysis of Financial Condition and Results of Operations inthe Group’s Form 10-K for the year ended December 31, 2023. There have been no material changes to our critical accounting estimates as disclosed in the Form 10-K for the year ended December 31, 2023.

Current wording

Our critical accounting estimates include "Reserve for Losses and Loss Adjustment Expenses", "Premiums Written and Earned", "Ceded Reinsurance and Unpaid Losses and Loss Adjustment Expenses Recoverable", and "Fair Value of Investments" and are discussed in Management’s Discussion and Analysis of Financial Condition and Results of Operations in the Group’s Form 10-K for the year ended December 31, 2024. There have been no material changes to our critical accounting estimates as disclosed in the Form 10-K for the year ended December 31, 2024.

Previous wording

(3) Underwriting income (loss) is a non-GAAP financial measure as defined in Item 10(e) of SEC Regulation S-K. Refer to 'Management’s Discussion and Analysis of Financial Condition and Results of Operations – Non-GAAP Measures' for further details.

Current wording

(1) Third party fee income is a non-GAAP financial measure as defined in Item 10(e) of SEC Regulation S-K. Refer to 'Management’s Discussion and Analysis of Financial Condition and Results of Operations – Non-GAAP Measures' for further details.

Previous wording

(2) Other underwriting expenses is a non-GAAP financial measure as defined in Item 10(e) of SEC Regulation S-K. The reconciliation to general and administrative expenses, the most comparable GAAP financial measure, also included corporate expenses of $14.1 million, and $18.7 million for the three months ended September 30, 2024 and 2023, respectively. Refer to 'Management’s Discussion and Analysis of Financial Condition and Results of Operations – Non-GAAP Measures' for further details.

Current wording

(2) Other underwriting expenses is a non-GAAP financial measure as defined in Item 10(e) of SEC Regulation S-K. The reconciliation to general and administrative expenses, the most directly comparable GAAP financial measure, also included corporate expenses of $13.0 million, and $11.5 million for the three months ended March 31, 2025 and 2024, respectively. Refer to 'Management’s Discussion and Analysis of Financial Condition and Results of Operations – Non-GAAP Measures' for further details.

Previous wording

Gross premiums written Gross premiums written were $553.4 million and $474.1 million for the three months ended September 30, 2024 and 2023, respectively. The increase in gross premiums written was primarily driven by our casualty, specialty and property reinsurance and property insurance classes. The increase was a result of new business, increased participations on existing business and a strong rate environment across multiple classes of business.

Current wording

Gross premiums written Gross premiums written were $843.3 million and $721.9 million for the three months ended March 31, 2025 and 2024, respectively. The increase in gross premiums written was primarily driven by our casualty and property reinsurance classes and specialty, property and casualty insurance classes, partially offset by a decrease in our specialty reinsurance classes. The increase was as a result of growth in both new and existing business and an increase in reinstatement premiums for the three months ended March 31, 2025.

Previous wording

Underwriting results The combined ratio was 93.6% and 92.6% for the three months ended September 30, 2024 and 2023, respectively. The increase was primarily driven by an increase in the catastrophe loss ratio, partially offset by a decrease in the other underwriting expense ratio, attritional loss ratio and acquisition cost ratio.

Current wording

Underwriting results The combined ratio was 111.6% and 91.5% for the three months ended March 31, 2025 and 2024, respectively. The increase was primarily driven by an increase in the catastrophe loss ratio and a modest increase in the acquisition cost ratio, partially offset by a decrease in the attritional loss ratio and a decrease in the other underwriting expense ratio.

Previous wording

Attritional loss ratio - current year for the nine months ended September 30, 2024 was 53.9% compared to 51.8% for the nine months ended September 30, 2023, an increase of 2.1 percentage points. The increase was primarily driven by losses of $37.9 million, or 3.0 points, arising from the Francis Scott Key Baltimore Bridge collapse, which impacted our insurance and reinsurance classes in both our International and Bermuda segments.

Current wording

Attritional loss ratio - current year for the three months ended March 31, 2025 was 51.9% compared to 57.2% for the three months ended March 31, 2024, a decrease of 5.3 percentage points. The decrease was primarily driven by the absence of large losses for the three months ended March 31, 2025, compared to $37.9 million of losses arising from the Francis Scott Key Baltimore Bridge collapse, which impacted our insurance and reinsurance classes in both our International and Bermuda segments for the three months ended March 31, 2024.

Previous wording

Attritional loss ratio - prior year for the nine months ended September 30, 2024 was an unfavorable 0.6% compared to favorable 0.4% for the nine months ended September 30, 2023, an increase of 1.0 percentage point. The attritional loss ratio - prior year for the nine months ended September 30, 2024 was primarily driven by unfavorable development in casualty classes in both our International and Bermuda segments and specialty insurance classes in our International segment, partially offset by favorable development in our International and Bermuda property classes. In addition, casualty business protected by the LPT discussed in Note 7, Reinsurance, benefited from favorable development in the underlying reserves of $1.4 million and $1.3 million in amortization of the associated deferred gain, for a total net positive earnings impact of $2.7 million. The attritional loss ratio - prior year for the nine months ended September 30, 2023 was primarily driven by favorable prior year development in specialty classes in the International and Bermuda segments, partially offset by unfavorable development in our Bermuda property and casualty classes. In addition, casualty business protected by the LPT discussed in Note 7, Reinsurance, benefited from $2.5 million in amortization of the associated deferred gain and favorable development in the underlying reserves of $1.5 million, for a total net positive earnings impact of $4.0 million.

Current wording

Attritional loss ratio - prior year for the three months ended March 31, 2025 was a favorable 2.9% compared to an unfavorable 3.1% for the three months ended March 31, 2024, a decrease of 6.0 percentage points. The attritional loss ratio - prior year for the three months ended March 31, 2025 was primarily driven by favorable development in both our International and Bermuda specialty and property classes. In addition, casualty business protected by the loss portfolio transfer ("LPT") discussed in Note 6, Reinsurance, benefited from favorable development in the underlying reserves of $1.0 million, which was partially offset by a change in the deferred gain of $0.5 million, for a total net positive earnings impact of $0.5 million. The attritional loss ratio - prior year for the three months ended March 31, 2024 was driven by unfavorable development in specialty classes in both our International and Bermuda segments, primarily related to two specific large losses, partially offset by various smaller reserve releases across classes as a result of reduced loss estimates and benign claims experience. In addition, casualty business protected by the LPT benefited from $0.9 million in amortization of the associated deferred gain, partially offset by unfavorable development in the underlying reserves of $0.1 million, for a total net positive earnings impact of $0.8 million.

Previous wording

For the nine months ended September 30, 2024, gains in TSHF were led by macroeconomic trading in FTV. Within FTV, gains were achieved in equities, commodities, fixed income, and credit, while losses were experienced in currencies. TSHF also saw gains from single name equities trading within STV and ESTV. In single name equities trading, gains were led by U.S. equities within STV, followed by non-U.S. equities within ESTV. Within ESTV, East Asia, Europe, Pan-America and China all made positive contributions to gains, in decreasing order.

Current wording

For the three months ended March 31, 2024, gains in TS Hamilton Fund were led by macroeconomic trading in Two Sigma Futures Portfolio, LLC ("FTV"). Within FTV, equities, commodities, fixed income, currencies, and credit all made positive contributions to returns, in decreasing order. TS Hamilton Fund also received positive contributions from single name equities trading. In single name equities trading, gains were led by U.S. equities within Two Sigma Spectrum Portfolio, LLC ("STV"), followed by non-U.S. equities within Two Sigma Equity Spectrum Portfolio, LLC ("ESTV"). Within ESTV, East Asia, Europe, Pan-America, and China all made positive contributions to returns, in decreasing order.

Previous wording

Total net realized and unrealized gains (losses) on investments and net investment income (loss) - other returned income of $118.8 million and $19.2 million for the nine months ended September 30, 2024 and 2023, respectively. Income for the nine months ended September 30, 2024 was primarily driven by investment income on higher yielding assets and positive mark-to-market returns as a result of decreasing U.S. treasury interest rates in the period. Income for the nine months ended September 30, 2023 was primarily driven by investment income on higher yielding assets, partially offset by negative price returns as a result of rising U.S. treasury interest rates.

Current wording

Total net realized and unrealized gains (losses) on investments and net investment income (loss) - other, returned income of $63.8 million and $5.2 million for the three months ended March 31, 2025 and 2024, respectively. Income for the three months ended March 31, 2025 was primarily driven by investment income on a larger portfolio of higher yielding assets and positive mark-to-market returns in the first quarter of 2025. Income for the three months ended March 31, 2024 was primarily driven by investment income on higher yielding assets, largely offset by negative price returns as a result of rising U.S. treasury interest rates in the first quarter of 2024.

Previous wording

We have determined our reportable business segments based on the information used by management in assessing performance and allocating resources to underwriting operations. We have identified two reportable business segments - International and Bermuda. Each of our identified reportable segments has a Chief Executive Officer who is responsible for the overall profitability of their segment and who regularly reports and is directly accountable to the chief operating decision maker: the Chief Executive Officer of the consolidated group.

Current wording

We have determined our reportable business segments based on the information used by management in assessing performance and allocating resources to underwriting operations. We have identified two reportable business segments - International and Bermuda. Each of our identified reportable segments has a Chief Executive Officer who is responsible for the overall profitability of their segment and who regularly reports and is directly accountable to the chief operating decision maker ("CODM"): the Chief Executive Officer of the consolidated group. The CODM's responsibilities include providing leadership to all levels of employees; developing culture, values, and ethos; setting the Company's strategy, vision and direction; and overall responsibility for the success and profitability of the Company, including evaluating segment performance.

Previous wording

We evaluate the performance of reportable segments based on their respective underwriting income or loss. Underwriting income or loss is calculated as net premiums earned less losses and loss adjustment expenses, acquisition costs, and other underwriting expenses (net of third party fee income). General and administrative expenses not incurred by the reportable segments are included in corporate and other expenses as part of the reconciliation of net underwriting income or loss to net income or loss attributable to common shareholders. As we do not manage our assets by reportable segment, investment income and assets are not allocated to reportable segments.

Current wording

The CODM evaluates reportable segment performance based on the segments' respective underwriting income or loss. Underwriting income or loss is calculated as net premiums earned less losses and loss adjustment expenses, acquisition costs, and other underwriting expenses, net of third party fee income. General and administrative expenses not incurred by the reportable segments are included in corporate and other expenses as part of the reconciliation of net underwriting income or loss to net income or loss attributable to common shareholders. As we do not manage our assets by reportable segment, investment income and assets are not allocated to reportable segments.

Previous wording

Corporate includes net realized and unrealized gains (losses) on investments, net investment income (loss), other income (loss) not incurred by the reportable segments, net foreign exchange gains (losses), general and administrative expenses not incurred by the reportable segments, amortization of intangible assets, interest expense, and income tax expense (benefit).

Current wording

Corporate includes net realized and unrealized gains (losses) on investments, net investment income (loss), net foreign exchange gains (losses), general and administrative expenses not incurred by the reportable segments, amortization of intangible assets, interest expense, and income tax expense (benefit).

Previous wording

Net premiums earned increased by $46.6 million, or 26.1%, from $178.6 million for the three months ended September 30, 2023 to $225.2 million for the three months ended September 30, 2024. The increase was primarily driven by growth in casualty and property insurance classes and specialty insurance and reinsurance classes. Casualty insurance growth was primarily driven by U.S. excess and surplus lines, mergers & acquisitions, professional lines, environmental and U.S. energy; property insurance growth was driven by property binders; specialty insurance growth was primarily driven by accident & health and political violence; and specialty reinsurance growth was primarily attributable to surety reinsurance.

Current wording

Net premiums earned increased by $43.8 million, or 22.2%, from $196.8 million for the three months ended March 31, 2024 to $240.6 million for the three months ended March 31, 2025. The increase was primarily driven by growth in our casualty, specialty and property insurance classes. Casualty insurance growth was primarily driven by U.S. excess and surplus lines, mergers & acquisitions, and cyber; specialty insurance growth was primarily driven by accident & health, marine & energy, and fine art & specie; and property insurance growth was primarily driven by property binder business.

Previous wording

Third party fee income increased by $2.1 million, or 97.2%, from $2.1 million for the three months ended September 30, 2023 to $4.2 million for the three months ended September 30, 2024. The increase was primarily due to favorable terms of a renewed syndicate management arrangement and an increase in consortium fees.

Current wording

Third party fee income increased by $0.7 million, or 20.8%, from $3.6 million for the three months ended March 31, 2024 to $4.3 million for the three months ended March 31, 2025. The increase was primarily due to an increase in consortium fees and syndicate management fees.

Previous wording

The loss ratio for the nine months ended September 30, 2024 was 58.7%, compared to 58.9% for the nine months ended September 30, 2023, a decrease of 0.2 percentage points. The modest decrease was primarily driven by lower prior year attritional loss development, partially offset by a higher current year attritional loss ratio for the nine months ended September 30, 2024.

Current wording

The loss ratio for the three months ended March 31, 2025 was 60.6%, compared to 59.0% for the three months ended March 31, 2024, an increase of 1.6 percentage points. The increase was primarily driven by a higher current year catastrophe loss ratio, partially offset by a lower current year attritional loss ratio and a favorable prior year development loss ratio for the three months ended March 31, 2025.

Previous wording

Attritional loss ratio - prior year for the nine months ended September 30, 2024 wasan unfavorable 0.3% compared to a favorable 4.3% for the nine months ended September 30, 2023, an increase of 4.6 percentage points. The unfavorable attritional loss ratio - prior year for the nine months ended September 30, 2024 was primarily driven by unfavorable development in specialty insurance classes, impacted by two large losses, and casualty insurance classes, impacted by one specific large loss, partially offset by favorable development in our property insurance and reinsurance classes. In addition, casualty business protected by the LPT discussed in Note 7, Reinsurance, benefited from favorable development in the underlying reserves of $1.4 million and $1.3 million in amortization of the associated deferred gain, for a total net positive earnings impact of $2.7 million.

Current wording

Attritional loss ratio - prior year for the three months ended March 31, 2025 was a favorable 3.6% compared to an unfavorable 2.9% for the three months ended March 31, 2024, a decrease of 6.5 percentage points. The favorable attritional loss ratio - prior year for the three months ended March 31, 2025 was primarily driven by favorable development in specialty reinsurance classes and property and specialty insurance classes. In addition, casualty business protected by the LPT discussed in Note 6, Reinsurance, benefited from favorable development in the underlying reserves of $1.0 million, which was partially offset by a change in the deferred gain of $0.5 million, for a total net positive earnings impact of $0.5 million.

Previous wording

Other underwriting expenses were $99.3 million for the nine months ended September 30, 2024, an increase of $9.7 million, or 10.8%, compared to $89.6 million for the nine months ended September 30, 2023. The increase was primarily driven by increases in headcount as we built out underwriting teams supporting the corresponding increase in premium volume, and certain growth related professional and IT costs.

Current wording

Other underwriting expenses for the three months ended March 31, 2025 were $35.6 million, an increase of $4.4 million, or 14.2%, compared to $31.2 million for the three months ended March 31, 2024. The increase was primarily driven by an increase in salary and compensation costs and an increased headcount as we continued to build out underwriting teams supporting the corresponding increase in premium volume, and certain growth related IT and professional costs.

Previous wording

The other underwriting expense ratios for the three months ended September 30, 2024 and 2023 decreased over the same period from 7.9% to 6.2%, as a result of the growth in premium base.

Current wording

The other underwriting expense ratios for the three months ended March 31, 2025 and 2024 decreased from 14.0% to 13.0% as a result of the growth in premium base.

Previous wording

Net premiums earned for the nine months ended September 30, 2024 increased by $167.5 million, or 37.4%, from $447.6 million for the nine months ended September 30, 2023 to $615.2 million for the nine months ended September 30, 2024. The increase was primarily driven by new business, volume growth and rate increases in our casualty and property reinsurance classes. The most significant drivers of this increase were general liability, professional lines and property treaty classes.

Current wording

Net premiums earned increased by $69.9 million, or 37.1%, from $188.5 million for the three months ended March 31, 2024 to $258.4 million for the three months ended March 31, 2025. The increase was primarily driven by new business and volume growth in our casualty and property reinsurance classes. The most significant drivers of this increase were general liability, professional liability, and property treaty and quota share business. Property reinsurance classes also increased as a result of certain non-recurring reinstatement premiums related to the California wildfires.

Previous wording

Third party fee income increased by $6.0 million, from $0.3 million for the nine months ended September 30, 2023 to $6.4 million for the nine months ended September 30, 2024. The increase was primarily driven by certain performance based management fees recognized by Ada Capital Management Limited for services provided to Ada Re, Ltd.

Current wording

Third party fee income is generated by certain performance based management fees recognized by Ada Capital Management Limited for services provided to Ada Re, Ltd. and decreased by $3.6 million, from $3.9 million for the three months ended March 31, 2024 to $0.3 million for the three months ended March 31, 2025.

Previous wording

Attritional loss ratio - prior year for the three months ended September 30, 2024 was a favorable 1.5% compared to a favorable 5.3% for the three months ended September 30, 2023, an increase of 3.8 percentage points. The favorable attritional loss ratio - prior year for the three months ended September 30, 2024 was primarily driven by favorable development in property insurance and specialty reinsurance classes, partially offset by unfavorable development in certain casualty insurance classes, including one specific large loss. In addition, casualty business protected by the LPT discussed in Note 7, Reinsurance, recorded a gain of $1.1 million.

Current wording

Attritional loss ratio - prior year for the three months ended March 31, 2025 was a favorable 2.2%, compared to an unfavorable 3.2% for the three months ended March 31, 2024, a decrease of 5.4 percentage points. The favorable attritional loss ratio - prior year for the three months ended March 31, 2025 was primarily driven by favorable development in specialty and property reinsurance classes, partially offset by modest unfavorable development in certain casualty reinsurance classes.

Previous wording

The acquisition cost ratio for the nine months ended September 30, 2024 was 19.9%, compared to 19.8% for the nine months ended September 30, 2023. The modest increase was primarily driven by a change in the mix of business, including more proportional business written in our casualty reinsurance classes.

Current wording

The acquisition cost ratio for the three months ended March 31, 2025 increased to 20.9%, compared to 19.5% for the three months ended March 31, 2024. The increase was primarily driven by a change in the mix of business, including more proportional business written in our casualty reinsurance classes.

Previous wording

The other underwriting expense ratio for the three months ended September 30, 2024 and 2023 decreased over the same period from 16.5% to 13.3% , primarily as a result of the growth in the premium base.

Current wording

The other underwriting expense ratio for the three months ended March 31, 2025 and 2024 increased from 4.4% to 5.3%, primarily as a result of reduced performance based management fees, partially off-set by growth in the premium base.

Previous wording

For the nine months ended September 30, 2024, gains in TSHF were led by macroeconomic trading in FTV. Within FTV, gains were achieved in equities, commodities, fixed income, and credit, while losses were experienced in currencies. TSHF also saw gains from single name equities trading within STV and ESTV. In single name equities trading, gains were led by U.S. equities within STV, followed by non-U.S. equities within ESTV. Within ESTV, East Asia, Europe, Pan-America and China all made positive contributions to gains, in decreasing order.

Current wording

For the three months ended March 31, 2024, gains in TS Hamilton Fund were led by macroeconomic trading in FTV. Within FTV, equities, commodities, fixed income, currencies, and credit all made positive contributions to returns, in decreasing order. TS Hamilton Fund also received positive contributions from single name equities trading. In single name equities trading, gains were led by U.S. equities within STV, followed by non-U.S. equities within ESTV. Within ESTV, East Asia, Europe, Pan-America, and China all made positive contributions to returns, in decreasing order.

Previous wording

Total net realized and unrealized gains (losses) on investments and net investment income (loss) - other, returned income of $118.8 million and $19.2 million for the nine months ended September 30, 2024 and 2023, respectively. Income for the nine months ended September 30, 2024 was primarily driven by investment income on higher yielding assets and positive mark-to-market returns as a result of decreasing U.S. treasury interest rates in the period. Income for the nine months ended September 30, 2023 was primarily driven by investment income on higher yielding assets, partially offset by negative price returns as a result of rising U.S. treasury interest rates.

Current wording

Total net realized and unrealized gains (losses) on investments and net investment income (loss) - other, returned income of $63.8 million and $5.2 million for the three months ended March 31, 2025 and 2024, respectively. Income for the three months ended March 31, 2025 was primarily driven by investment income on a larger portfolio of higher yielding assets and positive mark-to-market returns in the first quarter of 2025. Income for the three months ended March 31, 2024 was primarily driven by investment income on higher yielding assets, largely offset by negative price returns as a result of rising U.S. treasury interest rates in the first quarter of 2024.

Previous wording

Foreign exchange losses of $6.0 million and gains $1.4 million for the three months ended September 30, 2024 and 2023, respectively, primarily related to the remeasurement of insurance-related assets and liabilities denominated in British Pounds, Euro, Japanese Yen, and Australian and Canadian Dollars.

Current wording

Foreign exchange losses of $2.5 million and $2.1 million for the three months ended March 31, 2025 and 2024, respectively, were primarily driven by the remeasurement of insurance-related assets and liabilities denominated in British Pounds, Euro, Japanese Yen, and Australian and Canadian Dollars.

Previous wording

Corporate expenses for the nine months ended September 30, 2024 were $41.8 million compared to $31.8 million for the nine months ended September 30, 2023, an increase of $10.0 million. The increase was primarily driven by certain variable performance based compensation costs, an increased headcount and an increase in professional fees associated with operating as a public company, partially offset by a decrease in VAP expense.

Current wording

Corporate expenses for the three months ended March 31, 2025 were $13.0 million, compared to $11.5 million for the three months ended March 31, 2024, an increase of $1.5 million. The increase was primarily driven by certain variable performance based compensation costs, partially offset by a lower Value Appreciation Pool expense.

Previous wording

Amortization of intangible assets of $5.2 million and $2.8 million for the three months ended September 30, 2024 and 2023, respectively, relates to internally developed software and intangible assets acquired in a business combination. Amortization expense increased due to the incremental expense associated with additional technology projects.

Current wording

Amortization of intangible assets of $3.9 million and $3.3 million for the three months ended March 31, 2025 and 2024, respectively, relates to internally developed software and intangible assets acquired in a business combination. The increase in amortization expense is primarily driven by the incremental expense associated with additional technology projects.

Previous wording

Interest expense of $17.1 million and $16.0 million for the nine months ended September 30, 2024 and 2023, respectively, relates to interest payments and certain administrative fees associated with our term loan and letter of credit facilities. The increase in interest expense was primarily driven by the increase in the Secured Overnight Financing Rate ("SOFR"), which underlies the floating rate associated with the term loan.

Current wording

Interest expense of $5.6 million and $5.7 million for the three months ended March 31, 2025 and 2024, respectively, relates to interest payments and certain administrative fees associated with our term loan and letter of credit facilities. The decrease in interest expense is primarily driven by the decrease in the Secured Overnight Financing Rate ("SOFR") which underlies the floating rate associated with the term loan.

Previous wording

Income tax expense for the three months ended September 30, 2024 was $3.0 million, compared to $2.4 million for the three months ended September 30, 2023, an increase of $0.6 million. Tax expense for both the three months ended September 30, 2024 and 2023 was primarily driven by withholding taxes on investment income from TS Hamilton Fund.

Current wording

Income tax expense for the three months ended March 31, 2025 was $3.2 million, compared to $0.6 million for the three months ended March 31, 2024, an increase of $2.6 million. Tax expense is primarily driven by withholding taxes on investment income from TS Hamilton Fund and income tax expense on earnings from our London, Dublin, and U.S. operations, partially offset by a decrease in valuation allowance.