HSR Premerger Notification
The federal antitrust premerger notification regime under the Hart-Scott-Rodino Act (15 U.S.C. § 18a). Parties to certain mergers and acquisitions must notify the FTC and DOJ Antitrust Division and observe a 30-day waiting period before closing. The 2026 "size of transaction" threshold is $133.9 million (effective February 17, 2026), with a "size of person" test for transactions under $535.5 million. Failure to file properly carries civil penalties up to $53,088 per day.
HSR premerger notification is the federal antitrust regime requiring parties to certain mergers and acquisitions to notify the Federal Trade Commission (FTC) and the Department of Justice Antitrust Division and observe a waiting period before consummating the transaction. Codified in the Hart-Scott-Rodino Antitrust Improvements Act of 1976, the regime gives the antitrust agencies an opportunity to review transactions for potential anticompetitive effects before closing. Thresholds and fees adjust annually based on changes in gross national product; 2026 thresholds took effect February 17, 2026.
The 2026 jurisdictional thresholds
Effective February 17, 2026, the HSR thresholds are: (1) Size of Transaction: $133.9 million (up from $126.4 million in 2025). Transactions below this threshold are not reportable. (2) Size of Person: applies to transactions valued between $133.9 million and $535.5 million; one party must have annual net sales or total assets of $267.8 million, the other party $26.8 million. (3) All transactions above $535.5 million: reportable regardless of party size. The thresholds are adjusted annually based on changes in gross national product.
The 30-day waiting period
HSR-reportable transactions trigger an initial 30-calendar-day waiting period during which the parties may not close. The agencies use the period for preliminary review. Possible outcomes: (1) expiration of waiting period, most common; transaction can close; (2) early termination, formerly available on request; suspended by FTC in 2021 and not generally available in 2025-2026; (3) second request, formal request for additional information triggering an extended waiting period (typically 30 days from substantial compliance with the request). Second requests are time-consuming and expensive (often $1M+ in legal and economic-consulting fees) and signal substantive antitrust concern.
Filing fees (2026)
The 2026 filing fees, adjusted under the Merger Filing Fee Modernization Act (effective Feb. 17, 2026): six-tier structure based on transaction value, ranging from approximately $30,000 for the smallest reportable transactions to over $2.3 million for the largest. The fee is paid by the acquiring party at the time of filing. Failure to pay the correct fee can invalidate the filing and trigger penalties.
The revised HSR form (2025)
The FTC and DOJ implemented a substantially revised HSR form effective February 10, 2025, the first major form overhaul in decades. The revised form expanded required disclosures regarding competitive overlaps, vertical relationships, sales data, customer information, and document production. On February 12, 2026, a federal district court vacated the new form, with the court staying its decision for seven days. Subsequent litigation and appeals are ongoing as of early 2026; parties should confirm current form requirements with counsel before filing.
Common exemptions
Several exemptions apply to otherwise-reportable transactions: (1) acquisitions of certain assets in the ordinary course of business (e.g., inventory, used equipment); (2) acquisitions of certain real property and unproductive assets; (3) investment-only acquisitions by passive investors holding less than 10% (with limitations); (4) certain acquisitions of foreign assets and securities; (5) intracompany transactions; (6) certain bankruptcy reorganizations; (7) regulated industries with concurrent regulatory review (banks, telecoms in some contexts). Each exemption has specific technical requirements; counsel review is essential.
Civil penalties for noncompliance
Failure to file when required, or failure to observe the waiting period before closing, carries civil penalties up to $53,088 per day of noncompliance (as adjusted annually). Penalties accrue from the date the filing should have been made through the date corrective action is taken. The DOJ has actively enforced HSR violations in recent years, including multimillion-dollar settlements for failures to notify successive transactions, technical violations of waiting periods, and failures to update prior filings.
Section 8 of the Clayton Act
HSR practice often involves analysis of Section 8 of the Clayton Act, which prohibits interlocking directorates between competing corporations meeting threshold conditions. The 2026 Section 8 thresholds: $54,402,000 minimum size (capital, surplus, undivided profits) and $5,440,200 minimum competitive sales. The de minimis exceptions exclude small interlocks. Recent DOJ enforcement focus on Section 8 has expanded its practical importance for board appointments by activist investors and private equity sponsors.
For Texas businesses involved in M&A above the threshold range, HSR planning is gating. Best practice: (1) confirm jurisdictional thresholds at the contemplated closing date, not signing date; (2) engage HSR counsel early to identify exemptions and prepare filings; (3) build the 30-day waiting period (plus potential second-request extension) into transaction timelines; (4) prepare for revised-form requirements (subject to ongoing litigation); (5) consider antitrust risk allocation in transaction documents, break fees, "hell-or-high-water" covenants, divestiture obligations; (6) coordinate Section 8 analysis for board appointment provisions. For mid-market transactions below the threshold, HSR is typically not required but Section 7 of the Clayton Act remains in force, anticompetitive transactions can still be challenged regardless of reportability.
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