WEYERHAEUSER CO

We are subject to a multitude of statutes and regulations (collectively, "laws") in the operation of our businesses. We also participate in voluntary certification of our timberlands to ensure that we sustain their overall quality, including the protection of wildlife and water quality. Changes in these laws or certification standards can significantly affect our business.

REGULATIONS AFFECTING FORESTRY PRACTICES

In the United States, laws established by federal, state and local government agencies to protect, among other things, water quality, wetlands and other wildlife habitat could affect future harvests and forest management practices on our timberlands. Forest practice laws that affect present or future harvest and forest management activities in certain states include:

Each state in which we own timberlands has developed laws and/or best management practices to reduce the effects of forest practices on water quality and aquatic habitats. Additional and more stringent laws may be adopted by various state and local governments to achieve water quality standards, protect fish and wildlife habitats and human health, or achieve other public policy objectives.

In Canada, our forest operations are carried out on public timberlands under forest licenses with the provinces. All forest operations in Canada are subject to:

In Canada, 21 member companies of the Forest Products Association of Canada (FPAC), including Weyerhaeuser’s Canadian subsidiary, announced in May 2010 the signing of a Canadian Boreal Forest Agreement (CBFA) with nine environmental organizations. The CBFA applies to approximately 72 million hectares of public forests licensed to FPAC members and, when fully implemented, was expected to lead to the conservation of significant areas of Canada’s boreal forest and protection of boreal species at risk, in particular, woodland caribou. While the CBFA mandate came to an end in 2017, CBFA signatories continue to work on management plans with provincial governments and seek the participation of indigenous and local communities.

ENDANGERED SPECIES PROTECTIONS

In the United States, a number of fish and wildlife species that inhabit geographic areas near or within our timberlands have been listed as threatened or endangered under the federal Endangered Species Act (ESA) or similar state laws, including but not limited to:

Additional species or populations may be listed as threatened or endangered as a result of pending or future citizen petitions or petitions initiated by federal or state agencies. In addition, significant citizen litigation seeks to compel the federal agencies to designate "critical habitat" for ESA-listed species, and many cases have resulted in settlements under which designations will be implemented over time. Such designations may adversely affect some management activities and options. Restrictions on timber harvests can result from:

Such actions could increase our operating costs and affect timber supply and prices in general. To date, we do not believe that these measures have had, and we do not believe that in 2025 they will have, a significant effect on our harvesting operations. We anticipate that likely future actions will not disproportionately affect Weyerhaeuser as compared with comparable operations of U.S. competitors.

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In Canada:

The identification and protection of habitat and the implementation of range plans and land use action plans may, over time, result in additional restrictions on timber harvests and other forest management practices that could increase operating costs for operators of timberlands in Canada. To date, we do not believe that these Canadian measures have had, and we do not believe that in 2025 they will have, a significant effect on our harvesting operations. We anticipate that likely future measures will not disproportionately affect Weyerhaeuser as compared with similar operations of Canadian competitors.

FOREST CERTIFICATION STANDARDS

We operate in North America under the Sustainable Forestry Initiative® (SFI). This is a certification standard designed to supplement government regulatory programs with voluntary landowner initiatives to further protect certain public resources and values. SFI is an independent standard, overseen by a governing board consisting of:

Ongoing compliance with SFI may result in some increases in our operating costs and reduction of our timber harvests in some areas. There is also competition from other private certification systems, primarily the Forest Stewardship Council (FSC), coupled with efforts by supporters to further those systems by persuading customers of forest products to require products certified to their preferred system. Certain features of the FSC system could impose additional operating costs on timberland management. Because of the considerable variation in FSC standards, and variability in how those standards are interpreted and applied, if sufficient marketplace demand develops for products made from raw materials sourced from forests certified to these or other non-SFI standards, we could incur substantial additional costs for operations or need to reduce harvest levels in order to comply with such standards.

WHAT THESE REGULATIONS AND CERTIFICATION PROGRAMS MEAN TO US

The regulatory and non-regulatory forest management programs described above have:

We believe that these regulations and programs have not had, and in 2025 will not have, a significant effect on our total harvest of timber in the United States or Canada. However, these kinds of programs may have such an effect in the future. We expect we will not be disproportionately affected by these programs as compared with typical owners of comparable timberlands. We also expect that these programs will not significantly disrupt our planned operations over large areas or for extended periods.

CANADIAN INDIGENOUS RIGHTS

Many of the Canadian timberlands are subject to the constitutionally protected treaty or common-law rights of indigenous peoples of Canada. Most of British Columbia (B.C.) is not covered by treaties, and as a result the claims of B.C.’s indigenous peoples relating to forest resources have been largely unresolved. Nonetheless, the Supreme Court of Canada ruled that the Tsilhqot’in Nation holds indigenous title to approximately 1,900 square kilometers in B.C., the first time the court has declared title to exist based on historical occupation by indigenous peoples. Many indigenous groups continue to be engaged in treaty discussions with the governments of B.C., other provinces and Canada.

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Final or interim resolution of claims brought by indigenous groups can be expected to result in:

We believe that such claims will not have a significant effect on our total harvest of timber or production of forest products in 2025, although they may have such an effect in the future.

POLLUTION CONTROL REGULATIONS

Our operations are subject to various federal, state, provincial and local pollution control laws.

These laws, as well as market demands, impose controls with regard to:

Compliance with these laws and demands may involve capital expenditures or changes to operating procedures, which can increase operating costs. We cannot easily quantify the future amounts of capital expenditures we might have to make to comply with these laws and demands or the effects on our operating costs because in some instances compliance standards have not been developed or have not become final or definitive. In addition, it is difficult to isolate the environmental component of most manufacturing capital projects.

Our capital projects typically are designed to:

ENVIRONMENTAL CLEANUP

We are involved in the environmental investigation or remediation of numerous sites, predominantly resulting from historical legacy operations. Of these sites:

Our liability with respect to these various sites could range from insignificant to substantial. The amount of liability depends on the:

We spent approximately $5 million in 2024 and expect to spend approximately $14 million in 2025 on environmental remediation of these sites.

It is our policy to accrue for environmental remediation costs when we:

Based on currently available information and analysis, we believe it is reasonably possible that our costs to remediate all the identified sites may exceed our current accrual of $81 million by up to $212 million. This estimate of the upper end of the range of reasonably possible additional costs is much less certain than the estimates we currently are using to determine how much to accrue. The estimate of the upper range also relies on assumptions less favorable to us among the range of reasonably possible outcomes.

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REGULATION OF AIR EMISSIONS IN THE U.S.

The United States Environmental Protection Agency (EPA) has promulgated regulations under the federal Clean Air Act for air emissions from:

These regulations cover:

The EPA has issued several rules relating to MACT standards and GHG emissions from various energy-producing sources. Several court decisions have made the extent of applicability of these rules uncertain. Depending on the final outcomes of these decisions, these regulatory programs could affect our operations by increasing the cost of purchasing electricity or from mandated energy demand reductions that could apply to our mills and other facilities that we operate. The EPA is also expected to issue rules relating to biomass emissions, which is a significant source of energy at our mills. The effect of these existing and future emissions regulations, as well as related court decisions, on our operations remains uncertain. We continue to track and evaluate the litigation and regulatory developments but are not able to predict whether the regulations, when complete and implemented, will have a material effect on our operations. To address concerns about GHG as a pollutant, we closely monitor legislative, regulatory and scientific developments pertaining to climate change. For more information about the substantial progress we have made in reducing our GHG emissions, see our discussion in Carbon Record in the Environmental, Social and Governance (ESG) Practices – Environmental Stewardship section of this report.

Additional factors that could affect regulation of GHG emissions in the future include:

We believe these developments have not had, and in 2025 will not have, a significant effect on our operations. Although these measures could have a material adverse effect on our operations in the future, we expect that we will not be disproportionately affected by these measures as compared with owners of comparable operations. We maintain an active forestry research program to track and understand any potential effect from physical climate change related parameters that could affect the forests we own and manage and do not currently anticipate any near-term disruptions to our planned operations.

REGULATION OF AIR EMISSIONS IN CANADA

Our wood products facilities are regulated in Canada under provincial air quality regulations. The Canadian federal government has also proposed an air quality management system (AQMS) as a comprehensive national approach for improving air quality in Canada to go along with existing provincial air quality regulations. The AQMS includes:

In addition to these existing and proposed regulations, Environment and Climate Change Canada, a Canadian federal agency, released the Pan-Canadian Framework on Clean Growth and Climate Change, a "Greenhouse Gas Emission Framework." The framework put in place a national, sector-based GHG reduction program applicable to a number of industries, including ours.

All Canadian provincial governments:

Along with clean air regulations, British Columbia, a province in which we operate, has adopted a carbon tax and Alberta, where we also have operations, has a mandatory GHG emission reduction regulation.

Although these and related regulations and measures have not had, and we do not expect in 2025 that they will have, a material effect on our operations, they could in the future.

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REGULATION OF WATER IN THE U.S.

Our operations are regulated under the federal Clean Water Act, which regulates the discharge of pollutants into the waters of the U.S. This generally means obtaining permits for certain of our silviculture activities and our operating facilities and abiding by applicable restrictions. Federal agency rulemaking and related litigation under the act affects the definition of water subject to the act’s regulation. This, in turn, has affected the number of required federal and state permits in some areas of our operations and led to adjustments of our operational practices, particularly relating to the application of pesticides and herbicides on timberlands, which has increased operating costs.

State governments in the U.S. continue to promulgate total maximum daily load (TMDL) requirements for pollutants in water bodies that do not meet state or EPA water quality standards. State TMDL requirements may set:

Pending and future federal and state rulemaking, and judicial challenges thereto, could make application of the Clean Water Act, as well as comparable state laws, more or less costly to Weyerhaeuser, and we are not able to predict the final resolution of these matters. Although this and related regulations have not had, and we do not expect in 2025 that they will have, a material effect on our operations, they could in the future.

REGULATION OF WATER IN CANADA

In Canada, various levels of government have been working to address water issues including use, quality and management. Recent areas of focus include water allocation, regional watershed protection, protection of drinking water, water pricing and a national water quality index.

Changes to the Canadian Federal Fisheries Act have moved the focus of that legislation from habitat protection to fisheries protection and increased penalties. We expect further changes to these regulations, but we cannot predict the scope or potential effect, if any, on our operations. Although this and related Canadian regulations have not had, and we do not expect in 2025 that they will have, a material effect on our operations, they could in the future.