HSR Act Filings and Antitrust Merger Review in M&A:
A Deal Lawyer's Field Guide

1. Why Antitrust Sits on the Critical Path of Every Sizeable Deal

Antitrust clearance is not a checkbox. It is a condition to closing that neither party can waive unilaterally, that no amount of commercial goodwill between the principals can accelerate, and that the agencies are under no obligation to resolve quickly. In a deal where every other condition closes on schedule, a pending HSR review can hold parties in limbo for six months or longer while the clock runs on commitment letters, representation survival periods, and exclusivity arrangements. Deal lawyers who treat antitrust as a back-office administrative function rather than a front-of-mind deal-structuring variable expose their clients to avoidable schedule risk and, in serious cases, liability.

The critical path starts at term sheet. Whether a transaction is HSR-reportable determines when the waiting period begins. The filing trigger date, the correct identification of the acquiring and acquired persons, the applicable exemptions, and the fee tier are all questions that should be resolved before the parties execute a definitive agreement, not after. A transaction that is incorrectly structured as non-reportable, or where the filing is delayed because the parties did not identify the right ultimate parent entities during due diligence, creates post-signing exposure that is difficult to manage and expensive to cure.

The antitrust framework for merger review includes multiple layers. The HSR Act governs the procedural obligation to file and wait. The Clayton Act, Section 7, governs the substantive standard for whether the transaction is anticompetitive. The agencies enforce both. State attorneys general have independent authority to challenge mergers under both federal and state antitrust law. And foreign competition regulators operate their own review regimes on timelines that may not align with the HSR process. Managing all of these variables simultaneously, while maintaining momentum on the commercial transaction, requires a coordinated strategy that begins at signing and extends through closing and, in some cases, post-closing compliance periods measured in years.

The 2024 HSR form overhaul and the 2023 Merger Guidelines both signal that the agencies view their mandate broadly. More information is required at the front end. More transaction structures draw substantive scrutiny. And the burden of demonstrating that a transaction is unlikely to harm competition has, in practice, shifted toward the parties. That is the environment in which deal lawyers must plan, structure, and execute M&A transactions today.

2. HSR Thresholds: Size-of-Transaction and Size-of-Persons Tests

HSR filing is required when a transaction meets two independent tests: the size-of-transaction test and the size-of-persons test. Both must be satisfied for filing to be required, though one exception applies: transactions where the value exceeds a higher threshold require filing regardless of person size. Understanding how each test is calculated, and what assets count toward each, is the foundational layer of any HSR analysis.

The size-of-transaction test measures the value of the assets, voting securities, or non-corporate interests being acquired. For 2026, the base reportability threshold is $119.5 million (subject to annual adjustment; verify against the current Federal Register notice). A transaction must meet or exceed this figure to trigger a filing obligation. The calculation of transaction value is not always straightforward: it includes not only cash consideration at closing but also assumed liabilities, contingent payments such as earnouts, and any other consideration flowing from acquirer to seller as part of the same transaction. Assets acquired in a series of related transactions within 180 days may be aggregated under the rolling-acquisition rules.

The size-of-persons test applies to transactions that fall below the higher threshold that makes filing unconditional. The test asks whether one party has annual net sales or total assets of at least $239 million, and the other party has annual net sales or total assets of at least $23.9 million. These figures represent the 2026 adjusted thresholds and must be confirmed annually. Net sales and total assets are measured using the most recent regularly prepared financial statements, and the rules for which entities count toward each party's figures depend on the ultimate parent entity analysis described in Section 5.

Transactions above the higher absolute threshold, currently $478 million for 2026, require filing regardless of the size-of-persons test results. This unconditional filing requirement captures very large transactions regardless of the relative size of the parties and serves as a backstop to ensure that transactions with significant economic impact receive agency review.

3. 2026 Threshold Updates and Annual Indexing

Congress directed the FTC to adjust HSR thresholds annually based on changes in the gross national product, which in practice means the thresholds are revised each January and published in the Federal Register. The revised thresholds apply to transactions that close on or after the effective date, which is typically in late January or early February of each year. A transaction that signed in December but closes in March must be analyzed under the thresholds in effect at the time of closing, not the thresholds in effect at signing.

For 2026, the key thresholds are: the base size-of-transaction threshold at $119.5 million; the unconditional filing threshold at $478 million; the size-of-persons larger-party threshold at $239 million; and the size-of-persons smaller-party threshold at $23.9 million. Filing fees are also indexed and updated annually, with the 2026 fee structure reflecting adjustments to the six-tier schedule that Congress established in the Merger Filing Fee Modernization Act of 2022. That legislation both raised the top-tier fees for very large transactions and recalibrated the lower tiers, replacing the flat fee that had applied for decades to mid-size transactions.

Deal lawyers should build the annual threshold update into their engagement workflow. Applying the prior year's thresholds to a current-year transaction creates real risk: a transaction that would have been below the filing threshold in 2025 may be above it in 2026 if the threshold decreased (a downward adjustment is possible in years of GNP contraction), or vice versa. The safe practice is to pull the current Federal Register publication at the start of any HSR analysis and confirm the operative figures before advising a client on filing obligations.

The annual indexing system also means that a transaction structured to fall just below the threshold in one year may require filing if it is delayed into the next year when thresholds shift. Parties negotiating extended closing timelines in large transactions should account for this possibility when structuring the deal and setting the outside closing date. A threshold gap analysis at term sheet stage, updated at signing, is a minimal safeguard against this risk.

4. The 2024 Overhauled HSR Form and What It Now Asks

The FTC finalized a comprehensive overhaul of the HSR premerger notification form in October 2024, effective January 2025. The revised form represents the most significant expansion of required HSR disclosure since the Act was implemented in 1978. The practical effect is that filing preparation now takes substantially longer and requires more substantive input from deal principals and management teams, not just corporate counsel and paralegals assembling standard exhibits.

Four new disclosure requirements stand out. First, the form now requires a narrative explanation of the deal rationale: why the parties are entering into this transaction, what strategic objectives it serves, and what the acquiring party expects to gain. This is precisely the type of document that antitrust agency staff would have sought in a Civil Investigative Demand or Second Request, and its inclusion in the initial filing allows staff to evaluate competitive concern before deciding whether to open a full investigation. Second, the 360-degree officer and director overlap disclosure requires parties to identify all officers and directors of entities controlled by the acquiring person's ultimate parent entity and the acquired person's ultimate parent entity, including portfolio companies held by private equity fund families, revealing competitive overlaps that would not previously have been visible at initial filing.

Third, the form now requires identification of labor market overlaps by Standard Occupational Classification codes, reflecting the agencies' stated interest in monopsony effects and worker harm as cognizable antitrust injuries. Fourth, parties must disclose subsidies received from foreign governments or state-owned enterprises, a requirement that aligns with the agencies' stated concern about transactions influenced by foreign state actors in strategically important industries. Each of these new requirements demands coordination between antitrust counsel, deal counsel, HR, and government affairs personnel before the filing can be submitted.

The form also retains and in some respects expanded the documentary submission requirements, including the obligation to produce transaction documents, offering memoranda, analyses of competition prepared in connection with the transaction, and certain board-level materials. The combination of new narrative requirements and expanded documentary production means that experienced antitrust counsel should be engaged no later than the term sheet stage to structure the filing timeline correctly and avoid deficiency letters that restart the clock.

5. Acquiring Person, UPE, and Control Rules

The HSR Act and implementing regulations determine filing obligations at the level of the ultimate parent entity, not the immediate deal entity. The acquiring person is the UPE of the entity directly making the acquisition, and its identity governs which assets and revenues count toward the size-of-persons test and which entities must be disclosed in the filing. Getting the UPE analysis right is foundational: filing by the wrong entity, or failing to identify that a fund has a UPE with assets that change the fee tier, can result in a deficient filing that restarts the waiting period clock.

Control under the HSR regulations means holding 50 percent or more of an entity's outstanding voting securities, or having the right to designate 50 percent or more of the board of directors. The regulations trace control upward through the ownership chain until an entity is reached that is not itself controlled by any higher entity, and that entity is the UPE. For private equity funds, this analysis can be complex: a fund managed by a general partner that is controlled by a larger management company may have its UPE at the management company level, pulling in the revenues and assets of all other portfolio companies managed by that firm.

The HSR regulations treat minority interests carefully. An entity that holds 50 percent or less of voting securities, but exercises actual control through contractual rights such as veto power over major business decisions or the right to appoint a majority of the board, may still be treated as the controlling entity for HSR purposes under a facts-and-circumstances analysis. Venture capital and private equity investors should not assume that a sub-50-percent equity stake automatically avoids control treatment. The analysis turns on whether the investor, through the totality of its contractual and economic rights, exercises the functional equivalent of controlling the entity's management and policies.

The acquired person analysis follows similar principles: the UPE of the entity whose assets or voting securities are being acquired is the acquired person for HSR purposes. When a buyer acquires less than all of a company's assets or a partial equity stake, the analysis must also determine whether the acquisition crosses the percentage thresholds that trigger reporting at the 25 or 50 percent levels for subsequent acquisitions in the same issuer.

6. Exemptions: Investment-Only, Ordinary Course of Business, and Foreign

Not every transaction that meets the size-of-transaction and size-of-persons tests is reportable. The HSR regulations include a set of exemptions that remove certain acquisitions from the filing requirement even when threshold tests are satisfied. Identifying and properly documenting an applicable exemption is as important as identifying a filing obligation: an incorrectly claimed exemption, like a missed filing, exposes the parties to per-day civil penalties after the fact.

The investment-only exemption under 16 C.F.R. Section 802.9 exempts acquisitions of up to 10 percent of an issuer's voting securities where the acquisition is made solely for passive investment purposes and the acquirer does not intend to participate in the formulation, determination, or direction of basic business decisions. The exemption is narrow. Any board representation, observer rights that include access to competitive information, governance consent rights, or operational coordination with the target disqualifies the acquisition. The FTC has brought enforcement actions against investors who claimed the exemption while maintaining meaningful influence over the acquired company's operations.

The ordinary course of business exemption applies to acquisitions of goods or realty made in the ordinary course of business, meaning routine commercial transactions that do not result in the acquisition of an ongoing business or its competitive assets. Inventory purchases, standard real estate acquisitions for operational use, and commodity purchases fall within this exemption, but acquisitions of a competitor's product line, customer relationships, or manufacturing assets that constitute a business do not.

Foreign entity exemptions apply where both the acquiring and acquired persons are foreign and the transaction does not involve U.S. assets, U.S. revenues, or U.S. voting securities above specified thresholds. Cross-border transactions require a careful analysis of the nexus to U.S. commerce, because the HSR Act applies to foreign transactions that have U.S. competitive effects, and the foreign entity exemption has specific numerical triggers rather than a simple non-U.S.-nexus standard. Misapplying the foreign exemption to a transaction with meaningful U.S. revenue exposure is one of the more common HSR compliance errors in cross-border deals.

7. Calculating the Filing Fee Tier

The filing fee in an HSR transaction is paid by the acquiring person and is non-refundable. The Merger Filing Fee Modernization Act of 2022 replaced the prior three-tier fee schedule with a six-tier schedule that significantly increased fees for large transactions while adjusting the mid-range tiers. The six-tier structure in effect for 2026 is keyed to the value of the transaction as determined under the HSR Act's valuation rules, not the headline purchase price, and the tiers are subject to the same annual CPI indexing that applies to the substantive thresholds.

The 2026 fee schedule runs from $30,000 for transactions at the base filing threshold through $5.9 million for transactions above $11.1 billion. The middle tiers reflect the substantial increase Congress enacted for transactions between $500 million and $5 billion, where the prior flat fee of $280,000 has been replaced by tiers at $290,000 and $805,000 depending on where the transaction value falls. For private equity transactions where multiple assets are being acquired in a bundled deal, the fee applies to the aggregate value of the transaction, not to each asset separately.

The value of the transaction for fee purposes is determined under the same valuation rules that govern the size-of-transaction test: it includes cash consideration, assumed liabilities, contingent payments at their present value, and non-cash consideration at fair market value. When transaction value is difficult to determine precisely, for example in earnout-heavy deals where the ultimate price is highly variable, counsel must make a defensible valuation determination and document the analysis. Undervaluing the transaction to fall into a lower fee tier creates exposure that is disproportionate to the fee savings if the agency later challenges the valuation.

Only one filing fee is required per transaction. In transactions where both parties make separate filings, which is the standard structure, only the acquiring person's filing triggers the fee obligation. The parties can negotiate which entity technically serves as the acquiring person in a bilateral transaction structure to confirm that the fee obligation falls on the party whose economics make it most efficient to bear that cost, subject to the rules governing which party qualifies as the acquiring person under the HSR regulations.

8. The 30-Day Initial Waiting Period and Clock Mechanics

The HSR waiting period begins when both parties' filings are certified as substantially complete by the FTC. Certification occurs when the agency determines that the filing contains all required information and documents in the proper format. Deficient filings, missing attachments, or incorrectly identified entities result in a deficiency notice rather than certification, and the clock does not start until the deficiency is cured and a corrected filing is accepted. A rushed or incomplete filing does not buy the parties extra time; it simply delays the start of the waiting period while adding the burden of preparing and submitting a corrected package.

Once both filings are certified, the initial waiting period runs for 30 calendar days. If the reviewing agency takes no action before the period expires, the parties may close the transaction immediately after the waiting period ends. There is no affirmative clearance letter or approval document issued in routine cases: clearance is the absence of agency action within the waiting period. The parties should confirm the expiration date and time in writing with their antitrust counsel and not rely on their own calculation of the calendar.

Before the waiting period expires, the reviewing agency may issue a Second Request for additional information, which immediately tolls the clock. The clock resumes only after the parties certify substantial compliance with the Second Request, and a new 30-day period begins from that certification date. Alternatively, the agency may request a timing agreement, which is a voluntary extension of the waiting period in exchange for the agency's agreement to avoid seeking a preliminary injunction while discussions are ongoing. Timing agreements are common in transactions where the parties believe they can negotiate a remedy without full Second Request compliance.

The parties are prohibited from closing the transaction while the waiting period is running or after a Second Request has been issued but before the new waiting period commences. Closing during the waiting period is itself a violation of the HSR Act, separate from any substantive antitrust violation, and can result in civil penalties as well as an order unwinding the transaction. Deal teams should have a firm protocol for confirming waiting period status before issuing closing instructions.

9. Pull-and-Refile Strategy and When It Helps

A pull-and-refile is a legitimate and well-established practice under the HSR rules: the acquiring person withdraws the pending HSR filing before the waiting period expires and refiles, resetting the 30-day clock. Unlike early termination, which requires agency action to shorten the waiting period, a pull-and-refile simply extends the timeline by adding another 30-day period. That extension, counterintuitively, can be exactly what the parties need in certain commercial contexts.

The most common legitimate uses of pull-and-refile are: resetting the clock when the parties need more time to satisfy non-antitrust closing conditions such as regulatory approvals, financing, or target stockholder consents; giving the reviewing agency additional time to complete its review without the pressure of an imminent Second Request decision; and deferring a closing date that falls at a commercially inconvenient time such as a fiscal year-end, a holiday period, or a pending material disclosure event. Parties sometimes use pull-and-refile to supplement the initial filing with additional information the reviewing agency has informally indicated it would like to see, without waiting for a formal deficiency notice that would have the same clock-stopping effect.

Pull-and-refile does not reset the investigative status of the transaction. The reviewing agency retains all documents and information from the original filing and all informal contacts between agency staff and the parties' counsel. A pull-and-refile does not eliminate the risk of a Second Request if the agency has already identified competitive concerns. Parties who use the technique hoping to avoid a Second Request by giving the agency more time may succeed if the concerns are genuinely addressable through additional information, but they will not succeed if the agency has already substantively identified issues requiring formal investigation.

There is no limit on the number of times parties may pull and refile, but multiple refiles on the same transaction attract agency attention and can signal transaction distress. In practice, pull-and-refile is typically used once per transaction, and the parties negotiate the timing of the refile with antitrust counsel based on the commercial calendar and the agency's informal signals about the status of its review.

10. Second Requests: Scope, Cost, and Negotiation

A Second Request is a formal demand for additional information and documents issued by the reviewing agency under 15 U.S.C. Section 18a(e). Receipt of a Second Request means the agency has identified potential competitive concerns that it cannot resolve based on the initial HSR filing alone. It does not mean the transaction will be blocked: many transactions that receive Second Requests ultimately close, either after the agency determines that no competitive harm exists following review of the Second Request materials, or after the parties agree to a remedial divestiture or behavioral commitment.

The scope of a Second Request is defined by the document specifications, interrogatory-style questions, and custodian lists in the Request itself, and it is typically very broad. Parties should expect to produce all internal documents relating to the competitive overlap between the parties, documents assessing the acquisition's impact on pricing, capacity, innovation, or market share, materials relating to the parties' assessment of competition in the relevant markets, and communications between deal principals about the competitive rationale for the transaction. The Second Request also includes detailed financial data requests and requests for information about the parties' supply chain relationships, customer contracts, and geographic footprint.

Parties have the right to negotiate the scope of a Second Request with the reviewing agency through a process called meeting and conferring that typically occurs in the first several weeks after the Request is issued. Experienced antitrust counsel can often narrow the custodian list, reduce the time period covered by the document request, and limit the most burdensome specifications to categories where the agency has demonstrated a genuine need for the information. Second Request negotiation is an area where antitrust counsel's relationships with agency staff and knowledge of current agency priorities provide real economic value to the client.

The cost of Second Request compliance is transaction-specific but substantial. For mid-market deals, legal and e-discovery costs often range from $3 million to $15 million, and the management time commitment is significant. Before signing a definitive agreement, parties with potential antitrust overlap should model the cost and probability of a Second Request as part of their overall deal economics, and should negotiate a termination fee structure in the business combination agreement that allocates this risk appropriately.

11. Early Termination Status and Substitution Strategies

Early termination of the HSR waiting period has been suspended since February 2021, when the FTC announced it would no longer grant early termination requests due to resource constraints during a period of elevated merger activity. The suspension has continued through multiple fiscal years and as of April 2026 remains in effect. Parties cannot count on early termination as a tool for accelerating closing timelines.

Before the suspension, early termination allowed the reviewing agency to terminate the waiting period ahead of the 30-day expiration where the transaction presented no competitive issues. The practical benefit was limited to transactions where the parties needed to close on an accelerated schedule and where the agency was confident early in the review that no substantive concerns existed. The suspension did not alter the agency's substantive analysis; it simply means that the full 30 days must run in every transaction regardless of competitive complexity.

The practical substitution strategies for early termination are limited but worth understanding. First, parties may engage in informal pre-notification contact with the reviewing agency, sometimes called a fix-it-first conversation, where counsel presents the transaction's competitive profile before filing and receives informal agency guidance. This does not shorten the waiting period but can reduce the risk of a Second Request by ensuring the filing is targeted to the agency's actual concerns. Second, an expedited voluntary timing agreement can sometimes be negotiated with the agency where the transaction is straightforward and the parties agree to narrow commitments quickly, but this is agency-discretion territory.

Deal teams should plan for the full 30-day waiting period plus a buffer for deficiency resolution and any informal back-and-forth with the agency. For deals with a hard closing deadline, the filing date must be set backward from that deadline with sufficient margin to account for the full initial period, potential deficiency delays, and any preliminary informal engagement the parties choose to initiate. Filing dates that are engineered to clear exactly at an outside closing date leave no room for the routine delays that arise in any complex regulatory process.

12. Coordinating with DOJ, FTC, and State Attorneys General

HSR filings are made simultaneously with both the DOJ Antitrust Division and the FTC, but only one agency conducts the substantive review of any given transaction. The two agencies divide their merger review jurisdiction by industry: historically, the FTC has reviewed transactions in consumer products, pharmaceuticals, healthcare, and technology, while DOJ has reviewed transactions in telecommunications, banking, defense, energy, and transportation. The clearance process, during which the agencies determine which one will conduct the review, typically takes several days after filing and is a bilateral negotiation between the two agencies rather than a matter of choice for the parties.

State attorneys general play an increasingly important role in merger review, particularly in transactions affecting consumer markets with a strong geographic component. State AGs can challenge mergers under both federal antitrust law (Section 7 of the Clayton Act) and applicable state antitrust statutes, and they may act independently of the federal reviewing agency. A transaction cleared by the FTC or DOJ may still face a state-level challenge if the affected states believe the federal resolution was insufficient to protect local consumers. The California, New York, and Texas AG offices have been particularly active in this area, and transactions in healthcare, retail, and digital markets with significant state-level market shares should anticipate state-level engagement.

State AG coordination with the federal reviewing agency is common in significant transactions. State offices frequently participate as non-governmental observers in the federal review process, sharing information with the federal agency under memoranda of understanding and providing local market data that the federal agency may not have. Parties whose transactions involve state AG participation should engage state-specific antitrust counsel alongside their federal antitrust team, and should understand that settlement with the federal agency does not automatically resolve a state-level parallel investigation.

The practical implication for deal structuring is that antitrust risk cannot be assessed at the federal level alone. A complete antitrust risk analysis should identify the states where the parties have meaningful competitive overlap, assess the likelihood of state AG interest in those markets, and develop a state engagement strategy alongside the federal filing strategy. In transactions where state challenge risk is material, counsel should consider proactive outreach to affected state offices and should ensure that any federal consent order addresses the competitive concerns that would otherwise motivate a state challenge.

13. Gun-Jumping Risk: Pre-Closing Conduct and Information Sharing

Gun-jumping refers to conduct by the parties to a pending merger that effectuates the combination or transfers operational control before the waiting period expires and the transaction lawfully closes. Gun-jumping is a violation of the HSR Act and, separately, may constitute a violation of the Sherman Act Section 1 prohibition on agreements in restraint of trade, depending on the nature of the pre-closing coordination. The DOJ and FTC have both brought gun-jumping enforcement actions, and the penalties can be significant even in transactions that are ultimately cleared.

The line between legitimate pre-closing coordination and unlawful gun-jumping is not always clear, and the analysis depends on the specific conduct. Sharing competitively sensitive information such as pricing, customer lists, competitive strategy, and non-public financial projections with a competitor-acquirer before closing creates both gun-jumping risk and independent antitrust risk under the Sherman Act. The fact that the parties have signed a definitive agreement does not create a license to share information that would otherwise be prohibited between competitors. The signing of the agreement changes the parties' legal relationship but does not change their competitive status until the transaction actually closes.

Common gun-jumping fact patterns include: acquirers directing the target's pricing, hiring, or capital allocation decisions before closing; acquirers gaining access to the target's real-time operating systems or customer data before waiting period expiration; joint selling or marketing activities before closing; and integration activity that functionally combines operations, systems, or personnel before the legal transfer is complete. All of these activities, even when well-intentioned as preparation for a smooth Day 1 integration, can constitute gun-jumping if they result in the acquirer exercising de facto control over the target's competitive conduct.

The practical implication is that integration planning activities, while essential for operational success, must be carefully structured to avoid crossing the gun-jumping line. Deal teams and integration project managers need to understand what pre-closing activities are permissible, and antitrust counsel must be involved in designing the pre-closing governance structure to ensure that the target retains operational independence until closing.

14. Clean Teams, Firewalls, and Integration Planning

The mechanism that allows parties to share competitively sensitive information during the pre-closing period without violating the antitrust laws is the clean team protocol, also called a clean room or firewall arrangement. Under a clean team protocol, a limited group of individuals, typically consultants or employees who do not have ongoing competitive roles at either party, are designated as the clean team and are given access to competitively sensitive information subject to strict use restrictions. Clean team members may review the information for due diligence and integration planning purposes but may not share it with the competitive personnel at either party until after closing.

An effective clean team protocol includes a written agreement specifying who is on the clean team, what categories of information the clean team may access, how the information may be used, what outputs the clean team may produce and in what aggregated or anonymized form, and when the restrictions terminate. The protocol should be negotiated and documented before any competitively sensitive information is shared, and the parties' antitrust counsel should review and approve the protocol before it is implemented. A clean team protocol that is informally managed, incompletely documented, or breached by personnel who were not supposed to have access provides limited protection in an enforcement action.

Integration planning is a separate concern from information sharing. Parties to a pending merger have legitimate reasons to plan how they will combine their operations, systems, and workforces after closing, and detailed integration planning is essential to realizing the deal's value. The antitrust constraint is that integration planning must not result in actual integration activities before the waiting period expires. Planning documents, integration project plans, and organizational design work can proceed, but implementation: reassigning employees, terminating supplier contracts, changing pricing, or combining customer-facing operations, must wait until closing.

Clean team and firewall protocols should be documented in the definitive agreement or in a separate confidentiality agreement, and should be communicated clearly to all employees involved in due diligence and integration workstreams. Companies that have robust protocols clearly communicated to deal teams are better positioned to defend against gun-jumping allegations if a question arises, both because the protocol demonstrates good-faith compliance intent and because the documentation allows counsel to demonstrate that any information sharing was within the agreed parameters.

15. Remedies: Divestitures, Consent Orders, and Behavioral Commitments

When a reviewing agency identifies competitive concerns but believes the transaction can be cleared with modifications, it typically requires the parties to enter into a consent order that imposes structural or behavioral remedies as a condition of clearance. Structural remedies, principally divestitures of overlapping product lines, business units, or assets, are the agencies' preferred remedy for horizontal mergers. The agencies generally view structural remedies as more durable and easier to monitor than behavioral commitments, which require ongoing agency oversight of the parties' post-closing conduct.

A divestiture remedy requires the parties to sell specified assets to a buyer approved by the reviewing agency before or within a defined period after closing. The divested assets must be of sufficient scope to restore the competitive conditions that would have existed absent the merger in the relevant market. Upfront buyer agreements, in which the divestiture buyer is identified and approved before the merger closes, are increasingly preferred by the agencies because they eliminate the risk that a viable buyer cannot be found within the post-closing divestiture period. Consent orders with a post-closing divestiture period typically include a trustee provision that gives the agency authority to complete the divestiture at whatever price the market will bear if the parties fail to identify and close a divestiture sale within the required timeframe.

Behavioral consent orders are more common in vertical merger cases where structural remedies may not address the competitive concern. Common behavioral commitments include non-discrimination obligations requiring the merged entity to provide competitors with access to inputs or platforms on equivalent terms, firewall provisions requiring separation of competitively sensitive information between the merged business units, and most-favored-nation limitations. Behavioral remedies are subject to ongoing monitoring by an independent compliance monitor and carry the enforcement mechanism of civil contempt proceedings for violations, creating a long-term compliance burden for the parties.

The value of antitrust counsel in remedy negotiations comes from understanding what the agency will require to close its investigation and structuring the parties' remedy proposal to satisfy that standard at the lowest cost to deal value. Offering a well-crafted remedy package before the agency completes its investigation, rather than waiting for the agency to demand a specific remedy, gives the parties more control over the terms and often produces a more favorable outcome than reacting to an agency proposal under time pressure.

16. Hell-or-High-Water, Reasonable Best Efforts, and Reverse Termination Fees

The antitrust covenant in a merger agreement defines the acquirer's obligation to pursue regulatory clearance and determines the consequences if clearance is not obtained. The spectrum runs from "reasonable best efforts" or "commercially reasonable efforts" at one end to a "hell-or-high-water" commitment at the other, and the specific language negotiated in the definitive agreement has material economic and legal consequences.

A hell-or-high-water clause obligates the acquirer to do whatever is necessary to obtain antitrust clearance, including accepting any divestiture or behavioral remedy the agency requires, regardless of the cost to the merged entity's value. A pure hell-or-high-water commitment, without qualification, means the seller can compel the buyer to accept a consent order requiring divestiture of a significant portion of the acquired business if that is what the agency demands. Sellers negotiating with acquirers who face antitrust risk should push for this standard, while buyers should resist or qualify it with a materiality threshold that limits the divestitures or remedies they are required to accept.

Reasonable best efforts and commercially reasonable efforts standards are intermediate and fact-specific. Courts interpreting these standards generally require the party to take all reasonable steps that a commercially reasonable entity in its position would take to achieve the outcome, but the standard does not require the party to accept remedies that would fundamentally alter the deal economics or cause material harm to the acquirer's core business. The specific definition and any carve-outs from the efforts obligation should be negotiated explicitly, not left to judicial interpretation after a dispute arises.

A reverse termination fee is the financial backstop for antitrust failure: it is the amount the acquirer pays to the seller if the transaction fails to close because antitrust clearance is not obtained. The reverse termination fee is intended to compensate the seller for the opportunity cost of the deal process, including the time the target spent off the market during the waiting period. In transactions with significant antitrust risk, sellers should negotiate a reverse termination fee that reflects the realistic cost of a failed process, and the fee should be payable regardless of which party terminates the agreement when antitrust clearance cannot be obtained.

17. Vertical Mergers and the 2023 Merger Guidelines

The 2023 Merger Guidelines, issued jointly by the DOJ and FTC, addressed vertical mergers with a considerably more skeptical framework than the prior 2020 Vertical Merger Guidelines, which the agencies had rescinded in 2021. The 2023 Guidelines apply a unified analytical framework to horizontal and vertical transactions, treating market power concerns in any supplier-customer relationship as a legitimate basis for competitive concern.

The core vertical merger concern is foreclosure: a merged entity that controls an input or distribution channel may have both the ability and incentive to foreclose competitors from access to that input or channel, or to discriminate against them in ways that disadvantage their ability to compete. A media company that acquires a content distributor may favor its own content over competing content producers. A manufacturer that acquires a key component supplier may refuse to supply that component to competing manufacturers on competitive terms. The agencies evaluate these concerns through a market-by-market analysis that considers the merged entity's share of the relevant supply or distribution channel, the availability of alternative sources or channels, and the commercial incentives facing the merged entity after the transaction closes.

The 2023 Guidelines also identify access to competitively sensitive information as a distinct concern in vertical transactions. A supplier that obtains detailed knowledge of its customers' competitive plans, pricing, and customer relationships through the vertical merger can use that information to advantage its own downstream operations. Technology platform transactions frequently implicate this concern, where the platform's access to data about the operations of businesses that use the platform creates an information asymmetry that the agencies view as a cognizable competitive harm.

The practical implication for deal parties in vertical transactions is that the antitrust analysis must go beyond simple market share calculations in horizontal overlap markets. Counsel must model the foreclosure dynamics, assess the availability of alternative supply or distribution relationships for affected competitors, and evaluate the information-access concerns before advising a client on the antitrust risk profile of a vertical acquisition. Transactions that create integrated supply chains in concentrated industries require the most careful analysis.

18. Non-Reportable Transactions Still Subject to Section 7

The HSR Act creates a procedural filing obligation, but it does not create the substantive antitrust standard for merger review. That standard comes from Section 7 of the Clayton Act, which prohibits any acquisition where the effect may be substantially to lessen competition or tend to create a monopoly. Section 7 applies to all acquisitions with U.S. competitive effects, regardless of whether the transaction met the HSR filing thresholds. A transaction that is too small to require HSR filing can still be challenged under Section 7 if the agencies determine that it violates the substantive standard.

The agencies have become more aggressive in pursuing challenges to non-reportable transactions in recent years, particularly in technology and pharmaceutical markets where small acquisitions of nascent competitors can have significant long-run competitive effects. The FTC's retrospective review of tech platform acquisitions that were made when the target companies were small enough to avoid HSR thresholds demonstrated that some of those transactions had competitive effects that were not visible at the time of closing. This enforcement pattern has put deal parties on notice that below-threshold deal size does not provide a substantive antitrust safe harbor.

The agencies may challenge non-reportable transactions prospectively, through a pre-closing complaint seeking a preliminary injunction, or retrospectively, through post-closing litigation seeking divestiture and other relief. Post-closing Section 7 challenges are legally available for as long as the statute of limitations permits, and the DOJ and FTC have brought post-closing challenges in transactions that closed years earlier. The government is not subject to the four-year private party limitation period that applies to Section 7 claims.

Deal lawyers advising on transactions below the HSR thresholds should conduct a substantive Section 7 analysis as part of their risk assessment. A transaction that creates a dominant market position in a significant product or geographic market, even if it does not require HSR filing, should be evaluated for Section 7 risk, and that analysis should be documented in a privilege-protected memorandum that addresses the competitive effects and any procompetitive justifications for the transaction.

19. Foreign Merger Control Coordination and Timing

Transactions with international dimensions require parallel merger control filings in each jurisdiction where the parties meet the applicable notification thresholds. The European Union, United Kingdom, Germany, China, Canada, Brazil, Japan, Australia, and dozens of other jurisdictions each have their own merger control regimes with distinct filing thresholds, review timelines, substantive standards, and remedy authority. Managing these parallel filings in coordination with the HSR process is a logistical challenge that requires early planning and experienced multi-jurisdictional counsel.

The EU merger control process under the EU Merger Regulation provides one of the most important parallel review tracks for cross-border transactions. The EU applies a one-stop-shop principle under which transactions that meet the EU-level thresholds are reviewed by the European Commission rather than by individual member state authorities, simplifying the EU review process for large cross-border deals. EU Phase I review takes 25 working days, extensible for remedies; Phase II review takes an additional 90 working days, also extensible. Coordinating EU and U.S. timelines to permit a simultaneous global closing requires careful attention to each jurisdiction's procedural calendar.

China's merger control review under the Anti-Monopoly Law has become an increasingly important variable in global transactions. The State Administration for Market Regulation operates on timelines that are nominally shorter than U.S. and EU review periods but in practice can extend significantly through Phase II and conditional clearance processes. China's review of transactions involving semiconductor, technology, and strategic materials sectors has in some cases resulted in conditional clearance that imposes behavioral requirements on the global merged entity, affecting transaction economics beyond China's own market.

The critical path question in multi-jurisdictional transactions is which jurisdiction will be last to clear. The closing date cannot be set until all required clearances are in hand, and a delay in one jurisdiction can hold up a globally cleared transaction for months. Parties should identify the critical-path jurisdiction at the outset of the antitrust planning process, staff that jurisdiction's review accordingly, and consider whether voluntary filings in jurisdictions with optional notification regimes are worth pursuing to manage the risk of post-close investigation.

20. Post-Close Monitoring and Compliance Reporting

Antitrust compliance does not end at the closing table. Transactions cleared subject to consent orders require ongoing compliance for the duration of the order, which can run from a few years to a decade or more depending on the nature of the remedy. Structural consent orders requiring divestitures typically impose a fixed timeline for completing the divestiture and include compliance reporting obligations that require the parties to certify to the reviewing agency that the required assets have been sold to an approved buyer and that transition services are being provided on the agreed terms.

Behavioral consent orders, particularly those in vertical merger cases, require ongoing monitoring of the merged entity's conduct toward competitors who rely on the merged entity's inputs or distribution channels. The consent order typically specifies reporting obligations under which the merged entity must report to the agency any complaints from affected competitors, any changes to pricing or terms of access that affect the monitored products or services, and any material changes to the business units covered by the order. An independent compliance monitor, appointed with the agency's approval, reviews the merged entity's compliance on a regular schedule and reports directly to the agency.

Violations of HSR consent orders carry civil penalties of up to $51,744 per day under the current FTC penalty schedule, a figure that is adjusted annually for inflation. The agencies have brought civil penalty actions against companies that failed to complete divestitures within the required period, provided transition services that fell below the standards required by the order, or failed to maintain the firewalls required by behavioral commitments. The enforcement record demonstrates that agencies take consent order compliance seriously and are willing to litigate to enforce the terms.

A well-functioning post-close antitrust compliance program includes a dedicated compliance officer with direct oversight of the consent order obligations, a compliance calendar tracking all reporting deadlines, a documented process for investigating and reporting any potential violations to agency staff, and regular training for business unit leaders who operate in areas covered by the order. Companies that invest in compliance infrastructure at closing are better positioned to complete the consent order term without violations and to exit the monitoring period without adverse agency action.

Frequently Asked Questions