TPG Mortgage Investment Trust, Inc. (MITT) Business

ITEM 1. BUSINESS

Our company

TPG Mortgage Investment Trust, Inc. (the "Company," "MITT," "we," "us," and "our") is a residential mortgage REIT with a focus on investing in a diversified risk-adjusted portfolio of residential mortgage-related assets in the U.S. mortgage market. Our objective is to provide attractive risk-adjusted returns to our stockholders over the long-term, primarily through dividends and capital appreciation. Effective as of December 16, 2025, we changed our name from "AG Mortgage Investment Trust, Inc." to "TPG Mortgage Investment Trust, Inc."

We focus our investment activities primarily on acquiring and securitizing newly-originated residential mortgage loans within the non-agency segment of the housing market. We obtain our assets through Arc Home, LLC ("Arc Home"), our residential mortgage loan originator in which we own an approximate 66.0% interest, and through other third-party origination partners. We finance our acquired loans through various financing lines on a short-term basis and utilize TPG Inc.'s ("TPG") proprietary securitization platform to secure long-term, non-recourse, non-mark-to-market financing as market conditions permit. Through our ownership in Arc Home, we also have exposure to mortgage banking activities. Arc Home is a multi-channel licensed mortgage originator and servicer primarily engaged in the business of originating and selling residential mortgage loans while retaining the mortgage servicing rights associated with certain loans that it originates.

Our investment portfolio (which excludes our ownership in Arc Home) primarily includes Residential Investments and Agency RMBS. Currently, our Residential Investments primarily consist of Non-Agency Loans, Agency-Eligible Loans, Home Equity Loans and Non-Agency RMBS collateralized by these loan types, which we refer to as our target assets. In addition, we may also invest in other types of residential mortgage loans and other mortgage related assets.

As of December 31, 2025, our investment portfolio consisted of the following Residential Investments and Agency RMBS:

(1)These investments are included in the "Securitized residential mortgage loans, at fair value" and "Residential mortgage loans, at fair value" line items on the consolidated balance sheets.

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(2)These investments are included in the "Real estate securities, at fair value" line item on the consolidated balance sheets.

In addition, our investment portfolio includes commercial loans and commercial-mortgage backed securities ("CMBS") (collectively, the "Legacy WMC Commercial Investments") that were acquired in the WMC acquisition. The Legacy WMC commercial loans primarily include first lien commercial mortgage loan participations and are included in the "Commercial loans, at fair value" line item on the consolidated balance sheets. The Legacy WMC CMBS primarily include fixed-rate and floating-rate CMBS, secured by, or evidencing an ownership interest in, a single commercial mortgage loan or a pool of commercial mortgage loans, and are included in the "Real estate securities, at fair value" line item on the consolidated balance sheets. We expect to either hold the Legacy WMC Commercial Investments until maturity or opportunistically exit these investments.

Our primary sources of income are net interest income from our investment portfolio, changes in the fair value of our investments or hedge portfolio, and income from our investment in Arc Home. Net interest income consists of the interest income we earn on investments less the interest expense we incur on borrowed funds, inclusive of our cost or benefit of hedging. Income from our investment in Arc Home is generated through its mortgage banking activities which represents the origination and subsequent sale of residential mortgage loans and servicing income sourced from its mortgage servicing rights.

We were incorporated in Maryland on March 1, 2011 and commenced operations in July 2011. We conduct our operations to qualify and be taxed as a REIT for U.S. federal income tax purposes. Accordingly, we generally will not be subject to U.S. federal income taxes on our taxable income that we distribute currently to our stockholders as long as we maintain our intended qualification as a REIT, with the exception of business conducted in our domestic taxable REIT subsidiaries ("TRS") which are subject to corporate income tax. We also operate our business in a manner that permits us to maintain our exemption from registration under the Investment Company Act.

We are externally managed by AG REIT Management, LLC, a Delaware limited liability company (our "Manager"), a wholly-owned subsidiary of TPG (NASDAQ: TPG), a leading global alternative asset management firm.

Our Manager and TPG

We are externally managed by AG REIT Management, LLC, a Delaware limited liability company (our "Manager"), a wholly-owned subsidiary of TPG (NASDAQ: TPG), a leading global alternative asset management firm.

Pursuant to the terms of our management agreement, our Manager provides us with our management team, including our officers, along with appropriate support personnel. All of our officers are employees of TPG or its affiliates. We do not have any employees. Our Manager is at all times subject to the supervision and oversight of our Board of Directors and has only such functions and authority as our Board of Directors delegates to it. Our Manager has delegated to Angelo, Gordon & Co., L.P. ("TPG Angelo Gordon"), an affiliate of TPG, the overall responsibility of its day-to-day duties and obligations arising under our management agreement. TPG Angelo Gordon is the direct parent company of our Manager and is a registered investment adviser under the Investment Advisers Act of 1940, as amended.

Through our relationship with our Manager, we benefit from the expertise and relationships that TPG's Credit platform has established which provides us with resources to generate attractive risk-adjusted returns for our stockholders. Our management has significant experience in the mortgage industry and expertise in structured credit investments. We are able to leverage our Manager, along with our ownership interest in Arc Home, a vertically integrated origination platform, to access investment opportunities in the non-agency residential mortgage loan market. This strategic advantage has enabled us to grow our investment portfolio and remain active in the securitization markets, utilizing the TPG Credit platform's proprietary securitization platform to deliver non-agency investments to a diverse mix of investors.

WMC Acquisition

In December 2023, through a subsidiary, we completed our acquisition of Western Asset Mortgage Capital Corporation ("WMC"), a residential mortgage REIT (the "WMC Acquisition"). The WMC Acquisition grew the market capitalization of our company by 45% and was accretive to our earnings as a result of the $1.2 billion of investments acquired and substantial cost synergies realized.

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Our strategies

Our investment strategy

We rely on the experience of our Manager’s personnel to direct our investments. Our Manager’s investment philosophy is based on a rigorous and disciplined approach to credit analysis and is focused on fundamental in-depth research. Our Manager makes investment decisions based on a variety of factors, including expected risk-adjusted returns, yields, relative value, credit fundamentals, vintage of collateral, prepayment speeds, supply and demand trends, general economic and market sector trends, the shape of the yield curve, liquidity, availability of adequate financing, borrowing costs, macroeconomic conditions, and maintaining our REIT qualification and our exemption from registration under the Investment Company Act.

In accordance with investment guidelines adopted by our Board of Directors, our Manager evaluates specific investment opportunities as well as our overall portfolio composition. Our Manager makes day-to-day determinations as to the timing and allocations of our investment portfolio. These decisions depend upon prevailing market conditions and may change over time in response to opportunities available in different interest rate, economic and credit environments. As a result, we cannot predict the percentage of our assets that will be invested in any one of our approved asset classes at any given time. We may change our strategy and policies without a vote of our stockholders.

Our financing and hedging strategy

We use leverage to increase potential returns to our stockholders and to fund the acquisition of our investment portfolio. Our financing strategy is designed to increase the size of our investment portfolio by borrowing against the fair value of the assets in our portfolio. When acquiring residential mortgage loans and other assets, we finance our investments using repurchase agreements or facilities used to finance residential mortgage loans, which we refer to collectively as "financing arrangements." Upon accumulating a targeted amount of residential mortgage loans, we finance these assets utilizing long-term, non-recourse, non-mark-to-market securitizations as market conditions permit.

Repurchase agreements involve the sale and a simultaneous agreement to repurchase the transferred assets or similar assets at a future date. The amount borrowed generally is equal to the fair value of the assets pledged less an agreed-upon discount, referred to as a "haircut." The size of the haircut reflects the perceived risk associated with the pledged asset. Haircuts may change as our financing arrangements mature or roll and are sensitive to governmental regulations. Interest rates for our financing arrangements are determined based on prevailing rates (typically a spread over a base rate) corresponding to the terms of the borrowings, and interest is paid on a monthly basis or, for shorter term arrangements, at the end of the term. Repurchase agreements typically have a term of up to one year for loans and a term of 30 to 90 days for securities. Repurchase agreements are generally mark-to-market with respect to margin calls and recourse to us.

Our financing arrangements generally include customary representations, warranties, and covenants, but may also contain more restrictive supplemental terms and conditions. Although specific to each financing arrangement, typical supplemental terms include requirements of minimum equity and liquidity, leverage ratios, and performance triggers. In addition, some of the financing arrangements contain cross default features, whereby default under an agreement with one lender simultaneously causes default under agreements with other lenders. To the extent that we fail to comply with the covenants contained in these financing arrangements or are otherwise found to be in default under the terms of such agreements, the counterparty has the right to accelerate amounts due under the associated agreement. As of December 31, 2025, we are in compliance with all of our financial covenants.

We may also finance our business through public and private offerings of our equity and debt, including common and preferred stock issuances, senior and convertible debt instruments, depending on market conditions and other factors. During 2024, we issued senior unsecured notes which consist of $34.5 million principal amount 9.500% Senior Notes due February 2029 ("February 2029 Senior Unsecured Notes") and $65.0 million principal amount 9.500% Senior Notes due May 2029 ("May 2029 Senior Unsecured Notes" and together with the February 2029 Senior Unsecured Notes, the "Senior Unsecured Notes"). The February 2029 Senior Unsecured Notes were issued on January 26, 2024 in a public offering for net proceeds of approximately $32.8 million and the May 2029 Senior Unsecured Notes were issued on May 15, 2024 in a public offering for net proceeds of approximately $62.4 million. We may redeem the Senior Unsecured Notes in whole or in part at any time or from time to time at our option on or after the redemption date, upon not less than 30 days written notice to holders prior to the redemption date, at a redemption price equal to 100% of the outstanding principal amount of the Senior Unsecured Notes to be redeemed plus accrued and unpaid interest to, but excluding, the redemption date. The redemption date for the February 2029 Senior Unsecured Notes is February 15, 2026 and the redemption date for the May 2029 Senior Unsecured Notes is May 15, 2026.

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Subject to maintaining our qualification as a REIT and our Investment Company Act exemption, we utilize derivative instruments in an effort to hedge certain interest rate risk associated with the financing of our investment portfolio. Specifically, we seek to hedge our exposure to potential interest rate mismatches between the interest we earn on our investments and our borrowing costs caused by fluctuations in short-term interest rates. We may utilize interest rate swaps, swaption agreements, and other financial instruments such as short positions in to-be-announced securities. In utilizing leverage and interest rate derivatives, our objectives are to improve risk-adjusted returns and, where possible, to lock in, on a long-term basis, a spread between the yield on our assets and the costs of our financing and hedging.

Risk management strategy

The primary components of our risk management strategy are:

•Disciplined adherence to risk-adjusted return. Our Manager deploys capital when it believes that risk-adjusted returns are attractive. In this analysis, our Manager considers the initial net interest spread of the investment, the cost of hedging and our ability to optimize returns over time through rebalancing activities. Our Manager’s investment team has extensive experience implementing this approach.

•Concurrent evaluation of interest rate and credit risk. Our Manager seeks to balance our portfolio with both credit risk-intensive assets and interest rate risk-intensive assets. Both of these primary risk types are evaluated against a common risk-adjusted return framework.

•Active hedging and rebalancing of portfolio. Our Manager periodically evaluates our portfolio against pre-established risk tolerances and will take corrective action through asset sales, asset acquisitions, and dynamic hedging activities to bring the portfolio back within these risk tolerances. We believe this approach generates more attractive long-term returns than an approach that either attempts to hedge away a majority of the interest rate or credit risk in the portfolio at the time of acquisition, on the one end of the risk spectrum, or a highly speculative approach that does not attempt to hedge any of the interest rate or credit risk in the portfolio, on the other end of the risk spectrum.

•Strategic approach to increased risk. Our Manager’s investment strategy is to preserve our ability to extend our risk-taking capacity during periods of changing market fundamentals.

Investment policies

We comply with investment policies and procedures and investment guidelines that are approved by our Board of Directors and implemented by our Manager. Our Manager reports on our investment portfolio at each regularly scheduled meeting of our Board of Directors. Our independent directors do not review or approve individual investment, leverage or hedging decisions made by our Manager made in accordance with our investment policies.

Our investment policies include the following guidelines, among others:

•No investment shall be made that would cause us to fail to qualify as a REIT for federal income tax purposes;

•No investment shall be made that would cause us to be regulated as an investment company under the Investment Company Act; and

•Our investments will primarily be in our target assets.

Our target assets include the types of assets described in this Annual Report, under the heading "Our company" above, and our subsequent periodic filings with the SEC. Our investment policies may be changed by our Board of Directors without the approval of our stockholders.

Allocation policy

Consistent with its duties as a registered investment adviser, TPG Angelo Gordon has an investment allocation policy that governs the allocations of investment opportunities among itself and its clients, and this investment allocation policy also applies to our Manager and us. Pursuant to this policy, TPG Angelo Gordon and our Manager allocate investment opportunities among its clients in a manner which is fair and equitable over time and does not favor one client or group of clients.

Investment opportunities in our target assets may be allocated among us and TPG Angelo Gordon funds and accounts that are eligible to purchase such target assets. TPG Angelo Gordon considers the following factors, among others, when assigning investment opportunities among us and its other clients:

•Capital available for new investments;

•Existing ownership and target position size;

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•Investment objective or strategies;

•Risk or investment concentration parameters;

•Supply or demand for an investment at a given price level;

•Cash availability and liquidity requirements;

•Regulatory restrictions;

•Minimum investment size;

•Relative size or "buying power;"

•Regulatory and tax considerations, including the impact on our status under the Investment Company Act and REIT status; and

•Such other factors that may be relevant to a particular transaction.

In addition, our Manager may be precluded from transacting in particular investments in certain situations, including but not limited to situations where TPG Angelo Gordon or its affiliates may have a prior contractual commitment with other accounts or clients or as to which TPG Angelo Gordon or any of its affiliates possesses material, non-public information. Consistent with TPG Angelo Gordon’s fiduciary duty to all of its clients, it may give priority in the allocation of investment opportunities to certain clients to the extent necessary to meet regulatory requirements, client guidelines and/or contractual obligations. TPG Angelo Gordon or our Manager may determine that an investment opportunity is appropriate for a particular account, but not for another. In addition, TPG Angelo Gordon or its employees may invest in opportunities declined by our Manager for us. The investment allocation policy may be amended by TPG Angelo Gordon at any time without our consent. As the investment programs of the various entities and accounts managed by TPG Angelo Gordon change and develop over time, additional issues and considerations may affect TPG Angelo Gordon’s allocation policy and its expectations with respect to the allocation of investment opportunities. To the extent permitted by law, TPG Angelo Gordon is permitted to bunch or aggregate orders or to elect not to bunch or aggregate orders for a particular client account with orders for other accounts, notwithstanding that the effect of such bunching, aggregation or lack thereof may operate to the disadvantage of some clients.

There is an information barrier between the historical TPG business and TPG's Credit platform and certain TPG Real Estate products, including TPG Angelo Gordon and our Manager. While information barriers are designed to restrict the flow of information between certain businesses, such barriers may be breached, inadvertently or otherwise, including with respect to information regarding certain investment opportunities, deal pipelines and strategy, which could result in greater restrictions to our investment activities. TPG could in the future decide that it is advisable to adjust or fully remove the information barrier.

Operating and regulatory structure

REIT qualification

We have elected to be treated as a REIT under Sections 856 through 859 of the Internal Revenue Code of 1986, as amended (the "Code"). Our qualification as a REIT depends upon our ability to meet on a continuing basis, through actual investment and operating results, various complex requirements under the Code relating to, among other things, the sources of our gross income, the composition and values of our assets, our distribution levels and the diversity of ownership of our shares. We believe that we are organized in conformity with the requirements for qualification and taxation as a REIT under the Code, and that our manner of operation enables us to meet the requirements for qualification and taxation as a REIT.

We generally need to distribute at least 90% of our ordinary taxable income each year (subject to certain adjustments) to our stockholders in order to qualify as a REIT under the Code. Our ability to make distributions to our stockholders depends, in part, upon the performance of our investment portfolio.

As a REIT, we generally are not subject to U.S. federal income tax on our REIT taxable income that we distribute currently to our stockholders. If we fail to qualify as a REIT in any taxable year and do not qualify for certain statutory relief provisions, we will be subject to U.S. federal income tax at regular corporate rates and may be precluded from qualifying as a REIT for the subsequent four taxable years following the year during which we lost our REIT qualification. Accordingly, our failure to qualify as a REIT could have a material adverse impact on our results of operations and our ability to pay distributions, if any, to our stockholders. Even if we qualify for taxation as a REIT, we may be subject to some U.S. federal, state and local taxes on our income or property. In addition, any income earned by a domestic taxable REIT subsidiary, or TRS, will be subject to corporate income taxation.

Investment Company Act exemption

We conduct our operations so that we are not considered an investment company under Section 3(a)(1)(C) of the Investment Company Act. Under Section 3(a)(1)(C) of the Investment Company Act, a company is deemed to be an investment company if

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it is engaged, or proposes to engage, in the business of investing, reinvesting, owning, holding or trading in securities and owns or proposes to acquire "investment securities" having a value exceeding 40% of the value of its total assets (exclusive of U.S. government securities and cash items) on an unconsolidated basis, (the "40% test"). "Investment securities" do not include, among other things, U.S. government securities and securities issued by majority-owned subsidiaries that (i) are not investment companies and (ii) are not relying on the exceptions from the definition of investment company provided by Section 3(c)(1) or 3(c)(7) of the Investment Company Act.

Conducting our operations so that we are not to be considered an investment company under the Investment Company Act and the rules and regulations promulgated under the Investment Company Act and SEC staff interpretive guidance limits our ability to make certain investments. For example, these restrictions limit our and our subsidiaries’ ability to invest directly in Agency RMBS that represent less than the entire ownership in a pool of mortgage loans or debt and equity tranches of Non-Agency RMBS (in each case to the extent such interest are not retained interest in securitizations consisting of mortgage loans that were owned by us and such securitizations were not sponsored by us in order to obtain financing to acquire additional mortgage loans), certain real estate companies and assets not related to real estate.

Competition

Our net income depends, in large part, on our ability to acquire assets at favorable spreads over our borrowing and hedging costs. In acquiring our investments, we compete with other mortgage REITs, specialty finance companies, savings and loan associations, banks, mortgage bankers, insurance companies, mutual funds, institutional investors, investment banking firms, financial institutions, governmental bodies, hedge funds, and other entities. In addition, numerous REITs and specialty finance companies have similar asset acquisition objectives to ours. These other REITs and specialty finance companies increase competition for the available supply of our target assets suitable for purchase. Many of our competitors are significantly larger than we are, have greater access to capital and other resources and may have other advantages over us. Our competitors may include other entities managed by affiliates of our Manager. In addition, some of our competitors may have higher risk tolerances or different risk assessments, which could allow them to consider a wider variety of investments and establish more relationships than we can. Market conditions may attract more competitors, which may increase the competition for sources of financing. An increase in the competition for sources of financing could adversely affect the availability and cost of financing.

We have access to our Manager’s professionals and their industry expertise, which we believe provides us with a competitive advantage. These professionals help us assess investment risks and determine appropriate pricing for certain potential investments. These relationships enable us to compete more effectively for attractive investment opportunities. Despite certain competitive advantages, we may not be able to achieve our business goals or expectations due to the competitive risks that we face.

Human Capital Resources

We have no employees. All of our officers, and our dedicated or partially dedicated personnel, are employees of TPG or its affiliates. We are highly dependent upon TPG’s employees and, in turn, TPG’s ability to create a respectful and inclusive firm culture to attract and retain the necessary talent to provide services to our company and its assets.

TPG is a leading global alternative asset management firm, founded in San Francisco in 1992, with $303.0 billion of assets under management (as of December 31, 2025) and investment and operational teams around the world. For additional information regarding TPG and its human capital resources, see TPG's public filings with the SEC.

Available information

Our principal executive offices are located at 245 Park Avenue, 26th Floor, New York, New York 10167. Our telephone number is (212) 692-2000. Our website can be found at www.mitt.tpg.com. We make available free of charge, through the SEC filings section of our website, access to our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and any amendments to those reports, as are filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act, as well as our proxy statements with respect to our annual meetings of stockholders, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. Our Exchange Act reports filed with, or furnished to, the SEC are also available at the SEC’s website at www.sec.gov and can also be found on our website at www.mitt.tpg.com. The content of any website referred to in this Form 10-K is not incorporated by reference into this Form 10-K unless expressly noted.