ICLE Comments to the CLRC on Draft Language Options for Mergers and Acquisitions
The International Center for Law & Economics (“ICLE”) respectfully submits these comments on Memorandum 2026-29 (“the Memorandum”) in advance of the Commission’s August 17, 2026, meeting. ICLE is a nonprofit, nonpartisan global research and policy center founded to build the intellectual foundations for sensible, economically grounded policy. We have submitted comments earlier in this study on the Commission’s single-firm-conduct proposals,[1] and we have commented on merger-enforcement policy and proposed merger guidelines before the U.S. federal antitrust agencies and before competition authorities in Europe, Canada, and elsewhere.[2]
Our comments here address the operative text of the draft options. We will not relitigate the Memorandum’s account of the past half-century of federal enforcement, although we disagree with much of it. But whatever one’s view of that history, the draft language would not produce the results the Memorandum attributes to it.
The draft options share five features, each of which would make California a national outlier in merger law: (1) a codified structural presumption bearing a rebuttal standard federal courts abandoned decades ago; (2) statutory concentration thresholds that convert an enforcement-screening device into a decision rule; (3) a liability standard (“appreciable risk”) that deletes the substantiality element present in every version of the Clayton Act since 1914; (4) a command that courts treat a revisable federal enforcement-policy document as persuasive authority, even as federal case law is demoted to nonbinding status; and (5) a freestanding “tend to create a monopoly or monopsony” prohibition with no limiting principle. And the Commission would adopt all of this just months before SB 25 begins producing the first systematic data on the transactions a California merger statute would govern.
The Memorandum’s Own Account Does Not Support the Case for “Restoration”
The draft options rest on a shared premise: that federal courts have subverted the Clayton Act’s “may be substantially to lessen competition” standard with a more demanding one, and that California should legislate its way back to the original. The Memorandum’s own materials undercut that premise, however. As the Memorandum recounts, the 1950 Senate Report explained that the words “may be” mean the statute “would not apply to the mere possibility but only to the reasonable probability” of the proscribed effect.[3] Brown Shoe used the same formulation.[4] And so do the federal courts today—including the Ninth Circuit, whose decisions would most inform California courts. The Memorandum itself cites the Ninth Circuit’s 2025 decision in FTC v. Microsoft applying “reasonable probability,”[5] and Saint Alphonsus, under which no proof of actual anticompetitive effects is required at all, but under which it is still required that “the merger create an appreciable danger of such consequences in the future.”[6] The standard the Memorandum describes as the original one is the standard the governing case law imposes. There is nothing to “restore.”
The enforcement record also cuts against the idea that there is a problem that needs fixing. The Memorandum suggests that the 2023 Merger Guidelines’ enforcement “reset” has not materialized in practice, citing recent state challenges to federally approved transactions.[7] Those cases show states challenging mergers in federal court under the existing federal standard—and in Live Nation, the enforcers, California among them, won the verdict the Attorney General celebrated. Last month, California led a twelve-state coalition in filing suit under Section 7 to block Paramount Skydance’s acquisition of Warner Bros. Discovery and secured a temporary restraining order in record time.[8] Indeed, the combined shares alleged in that case—roughly 27 to 30 percent of the pleaded markets—track the share Philadelphia National Bank (PNB) itself found sufficient. In other words, whatever constrains California merger enforcement, on this record it is not the substantive standard. A new statute along the proposed lines will not add enforcement resources or better information about transactions. Rather, it will add uncertainty, and the costs of uncertainty fall on every transaction—including the overwhelming majority that are competitively benign or beneficial.
Codifying Philadelphia National Bank Would Freeze the Doctrine at the Point Federal Courts Found Unworkable
Subsection (c) of every option deems a merger that produces “an undue percentage share” and “a significant increase in . . . concentration” to lessen competition substantially “in the absence of evidence clearly showing” the contrary, and states that it “is intended to codify the holding in United States v. Philadelphia National Bank.”[9]
PNB remains good law, and structural evidence retains an established role in merger litigation. But the Memorandum treats the six decades of subsequent doctrine as an erosion of PNB. Those cases didn’t reject the structural presumption. What they actually did was relax the demanding “clearly showing” formulation for rebutting the presumption.
In United States v. Baker Hughes, the government argued that a Section 7 defendant can rebut a prima facie case only by a “clear showing.” The D.C. Circuit—in an opinion by then-Judge Thomas, joined by then-Judge Ruth Bader Ginsburg—rejected that standard as “devoid of support in the statute, in the case law, and in the government’s own Merger Guidelines.”[10] A defendant required to produce evidence “clearly” disproving future anticompetitive effects, the court explained, “must essentially persuade the trier of fact on the ultimate issue in the case,” collapsing the distinction between the burden of production, which shifts, and the burden of persuasion, which remains with the plaintiff throughout.[11] “Requiring a ‘clear showing’ in this setting would move far toward forcing a defendant to rebut a probability with a certainty.”[12] Yet that is the formulation subsection (c) would enact as California statutory text.
A judicially administered presumption can be adjusted as evidence accumulates. A statutory one cannot. The federal presumption has been reworked over six decades as courts learned when market shares predict anticompetitive effects and when they mislead.[13] But fixed in statutory text—and expressly tied to a 1963 holding—no California court could learn from experience and reweight the presumption, whatever the evidence in a given case showed, leaving only the meaning of “undue” and “significant” open to construction.
And the economic learning gives no reason for confidence in the 1963 formulation. The premise the PNB Court drew from the economics of its day—that concentration reliably predicts competitive harm—has not survived the subsequent half-century of empirical work. The staff’s own cited authority on the HHI notes that the measure’s “link to market power is equivocal.”[14] And when the federal agencies considered lowering their concentration thresholds in 2022, a group of economists including Aviv Nevo—who then became director of the FTC’s Bureau of Economics under Chair Lina Khan and helped produce the 2023 Guidelines—warned that the empirical literature couldn’t support such a move:
The existing body of research on this question is, today, thin and mostly based on individual case studies in a handful of industries. Our reading of the literature is that it is not clear and persuasive enough, at this point in time, to support a substantially different threshold that will be applied across the board to all industries and market conditions.[15]
A statute codifying a strong structural presumption in 2026 would erroneously enshrine an outdated economic premise that the economics profession has spent over half a century studying and finding wanting.
Statutory HHI Thresholds Would Convert a Screening Device into a Merits Rule, and Put Market Definition in Place of Competitive Effects
The option presented as “Basic Merger Framework and Federal Merger Guidelines” goes further, presuming unlawful any merger that produces an HHI above 1,800 with a change greater than 100 points, or a 30 percent share with a change greater than 100 points.[16]
Concentration thresholds in enforcement guidelines are screening devices; they tell the agencies which of the thousands of transactions notified each year warrant a closer look. In contrast, a statutory presumption of illegality is a decision rule. The draft converts one into the other, and it does so at threshold levels that are themselves outliers.
The 2010 Horizontal Merger Guidelines placed the presumption at an HHI of 2,500 with a change of 200;[17] the 2023 Guidelines lowered both numbers and added the 30-percent trigger, without new empirical support—exactly the change the Nevo comments cautioned against. Nor is the 30-percent trigger grounded in PNB: as the Congressional Research Service observed, the merger in that case involved an HHI increase of roughly 600—six times the Guidelines’ trigger—prompting doubts “whether the Guidelines’ approach is firmly rooted in existing doctrine.”[18]
The proposed lower thresholds would apply the presumption to ordinary transactions in markets that still have five or six real competitors. A merger between a firm with a 10-percent share and a firm with 6 percent produces a change in HHI of 120, and an HHI of 1,800 corresponds roughly to a market shared among five or six significant competitors. In any such market, then, the acquisition of a 6-percent rival by a 10-percent firm—a transaction no empirical literature identifies as systematically harmful—would be presumptively unlawful, with the burden on the parties to prove otherwise.
Moreover, because the HHI is computed within a defined relevant market, a low statutory threshold makes market definition outcome-determinative. The narrower the market a plaintiff alleges, the higher the shares and the more readily the presumption attaches. Litigation then turns on market boundaries rather than competitive effects, and market definition is the most manipulable stage of any antitrust case, as the divergent recent treatments of “accessible luxury handbags” and “premium mattresses” illustrate.[19] As Baker Hughes put the point: “The Herfindahl-Hirschman Index cannot guarantee litigation victories.”[20]
Further compounding the problem, the proposed rebuttal provision then makes the presumption virtually conclusive. Subdivision (e) permits rebuttal only by a preponderance showing “no likely anticompetitive effects”—proof of a negative—or a showing that harmful effects are de minimis and “clearly outweighed by the cognizable procompetitive benefits of the transaction in the same relevant market.”[21] Federal law has never required so much.
Subdivision (e) further enshrines the most constrained reading of PNB by recognizing only procompetitive benefits arising “in the same relevant market” in which harm is alleged.[22] That limitation would exclude real competitive benefits merely because they occur outside the market as pleaded by the plaintiff. It also gives market definition a further importance it shouldn’t have: the narrower the alleged market, the more benefits the defendant is forbidden to offer in response.
The limitation also claims more authority than its source provides. The in-market rule traces to PNB’s response to the banks’ “final contention”—that Philadelphia needed a larger bank to attract business and stimulate the region’s economic development. The Court refused to weigh that kind of claim: a merger is not saved “because, on some ultimate reckoning of social or economic debits and credits, it may be deemed beneficial,” a “value choice” the Court considered “beyond the ordinary limits of judicial competence.”[23] What the Court declined to entertain, in other words, was a non-competition-related justification—civic betterment offered as an offset to lost competition. It did not hold that evidence of a transaction’s competitive benefits ceases to count the moment those benefits cross a hypothetical market boundary. Subdivision (e) would enact that further step by statute, and in its most rigid available form.
Many mergers create benefits that don’t fit within a single product-market box. A transaction may accelerate commercialization, improve a platform or ecosystem, combine complementary technologies, place assets under better management, support follow-on investment, or make entry more attractive to other firms. Acquisitions of nascent or adjacent firms often entail acquisitions of firms that operate in different market from their acquirers, so the transaction’s benefits and its alleged harms almost by definition don’t arise in the same place.[24] Excluding such benefits by statute would require courts to assess only part of a transaction’s competitive effect and to ignore the rest even when it bears directly on whether the transaction, taken as a whole, promotes or harms competition.
To be sure, federal courts generally decline to offset harm in one market with benefits in another. But the general rule has never been the absolute one that subdivision (e) would make of it. The federal agencies’ own guidelines have long reserved discretion to credit out-of-market efficiencies “inextricably linked” to the relevant market.[25] Courts reach benefits spread across distinct customer groups through market definition itself—Ohio v. American Express requires both sides of a two-sided platform to be weighed within a single market—and nothing prevents a court from defining a market broadly enough that the efficiencies fall within it.[26] Recently, the court in the FTC’s monopolization case against Meta canvassed this “unsettled question” and permitted the defendant to present evidence of procompetitive effects outside the alleged market.[27] Daniel Crane argues that the rule “is best operationalized as a presumption . . . that can be rebutted based on compelling evidence in particular cases.”[28]
Whatever the right resolution, this is a question federal courts and commentators are actively working out. A statute answering it in the most restrictive available form would foreclose that development for California—codifying, once again, the 1963 high-water mark as if the ensuing sixty years had nothing to teach.
“Appreciable Risk of Lessening Competition More Than a De Minimis Amount” Is an Expansion, Not a Restoration, of the Section 7 Standard
Supporters present the “appreciable risk” option as recapturing Clayton Act Section 7’s original meaning. The Memorandum’s own history refutes that characterization, however. Substantiality has been an element of Section 7 continuously since 1914; the 1950 Celler-Kefauver amendments, as the Memorandum notes, merely unsplit an infinitive—“may be to substantially lessen” became “may be substantially to lessen.”[29] As the Celler-Kefauver legislative history makes clear, Congress was concerned that Section 7 not reach every acquisition between competitors,[30] and the resulting language required a reasonable probability of a substantial lessening of competition in a line of commerce. A standard that deletes “substantially” and substitutes “more than a de minimis amount” has no antecedent in any version of the Clayton Act.[31] Its actual source is Senator Klobuchar’s CALERA bill, which Congress has had before it since 2021 and has declined to enact.[32]
Substantiality is what separates Section 7 from an outright prohibition on horizontal acquisitions. As Judge Posner observed of the statutory “may be,” the term “should not be taken literally, for if it were, every acquisition would be unlawful.”[33] Every acquisition of one competitor by another eliminates some rivalry between the parties; that is what makes them competitors. A prohibition on transactions carrying an “appreciable risk” of a more-than-trivial lessening of competition therefore covers, on its face, nearly every horizontal transaction of any size—leaving the actual scope of liability to be set by enforcement discretion and by the settlement calculus of private treble-damages plaintiffs.[34]
The costs of such a standard would be real yet largely unobservable. A liability standard’s most significant effect is on transactions that are abandoned or never proposed. For the startups and early-stage firms that populate California’s technology and life-sciences sectors, acquisition is a principal channel through which investment is recouped and redeployed. Between 2004 and 2020, 92 percent of United States venture-backed exits were mergers or acquisitions.[35] A merger regime that deters acquisitions also deters the investment that precedes them.[36] The Commission has heard exactly this from California’s own life-sciences industry.[37]
And the cases cited in the Memorandum—Saint Alphonsus and Hospital Corp.—applied “appreciable danger” to particular facts; they did not turn that phrase into a general burden of proof, much less use it to dispense with substantiality.[38] Option Four simply lifts the adjective, “appreciable,” from those cases, while dropping the discussion of the specific and substantial harms the word was used to describe.
Revised subdivision (c) of Option Four deems a qualifying merger to create “an appreciable risk of lessening competition more than a de minimis amount” unless the defendant clearly shows that anticompetitive effects are unlikely. The defendant must therefore disprove a risk—that is, prove a negative about a probability. If (and when) courts are unable to give that burden a workable meaning, the purportedly rebuttable presumption becomes effectively conclusive.
If the Commission concludes that Section 7’s “may be” language needs clarification, the proposed alternative of a “reasonable probability” provision is the only option presented that clarifies the standard rather than changing it.[39] But still, we would urge two conditions. First, the provision should govern the court’s assessment of the record as a whole—including entry, efficiencies, and dynamic competition—rather than operating asymmetrically on the plaintiff’s showing alone. Second, it should not be paired with subsection (c): a codified presumption rebuttable only by “evidence clearly showing” would reinstate, in presumption form, the heightened-certainty regime the clarification is meant to disavow.
The Draft’s Treatment of Federal Authority Is Selective, and the Guidelines Provision Is Unsound by Design
The proposed purpose statement provides that federal case law “is not binding on California state courts” and may be considered persuasive only “to the extent [courts] find it consistent with California law.”[40] The revised version pending in AB 1776 goes further, describing federal interpretations as “at most instructive, not conclusive.”[41] The proposed text simultaneously commands that the 2023 Merger Guidelines “shall be considered persuasive authority and understood to complement and be harmonized with this section.”[42]
The combination is difficult to explain on any neutral principle. Decisions of Article III courts construing the very statutory language California proposes to borrow are demoted, while a policy statement of two federal executive agencies—one that binds no court, federal or state—is elevated. So far as we can discern, the discrepancy in treatment between these two bodies of federal authority is based on the direction in which each cuts and not on their respective legal persuasiveness.
The provision is also unsound on its own terms. Merger guidelines are enforcement-policy documents; they carry weight in litigation only insofar as they persuade courts that they accurately describe the law, and the agencies revise them—1968, 1982, 1992, 2010, 2023—in ways the Memorandum itself describes as reversals of enforcement philosophy.[43] A California statute tied inexorably to the 2023 edition guarantees divergence: When the federal agencies next revise their guidelines, California courts will be statutorily directed to a superseded document—recreating, in permanent form, the federal-state divergence the Memorandum elsewhere counts as a cost.[44]
And the instruction that the Guidelines be “harmonized with this section”[45] supplies no direction to a court confronting a conflict between the two. If the Commission’s aim is a California merger law that stands on its own foundations, incorporating by reference a revisable document produced by federal officials whom California neither appoints nor supervises is a strange way to achieve it.
We also note our continuing objection to the purpose statement itself, which directs courts to interpret the statute “liberally” in service of “maximizing” deterrence and of goals extending to “democratic, political, and social institutions.” We explained in our single-firm-conduct comments why it would be unwise “to untether California antitrust law from U.S. antitrust law’s error-cost framework, effects-based analysis, and consumer welfare standard.”[46] The provision does more damage in merger review than in conduct cases, because merger enforcement is predictive. A conduct case examines what a firm did. A merger case forecasts what a combination might do, and an instruction to resolve that uncertainty in one direction also affects every transaction that is never proposed.
The Freestanding “Monopoly or Monopsony” Prong Has No Limiting Principle
Subsection (b) of every option restates, as a freestanding prohibition, the “may be to tend to create a monopoly or monopsony” clause drawn from Section 7 and that subsection (a) already contains. Courts presume that statutory language is not redundant, so subsection (b) will be read to do independent work: to condemn acquisitions that could not be shown to lessen competition substantially, on the ground that they “tend” toward monopoly or monopsony “in any section of the state.” The provision contains no substantiality element, no threshold of any kind, and no definition of the markets—including local labor markets—in which the “tendency” is to be assessed.
Monopsony analysis is an area in which basic questions of market definition and measurement remain unsettled in the economic literature, as we detailed in our earlier comments.[47] A tendency-toward-monopsony prohibition of unbounded geographic granularity, uncertain composition, and enforceable in treble-damages actions, would place at legal risk routine acquisitions by any employer of local significance—hospitals, grocers, processors—without any showing of harm to competition.
The Commission Should Let SB 25 Produce a Record Before California Adopts a Liability Standard
California has only just enacted the legislative instrument that would tell the Commission what problem, if any, a California merger statute needs to solve. SB 25, the California Uniform Antitrust Premerger Notification Act, was signed on February 10, 2026, and requires qualifying HSR filers to provide their federal filings to the Attorney General beginning January 1, 2027.[48] No one today—including the Attorney General—knows how many California-affecting transactions that regime will surface, how many federal clearances California would wish to contest, or what that residual set of transactions looks like. Enacting a liability standard first and discovering the caseload afterward inverts the sensible order of operations, and it forfeits the opportunity to align the statute’s scope with SB 25’s thresholds. Indeed, the current draft attempts no alignment at all: it contains no size-of-transaction threshold, reaching acquisitions of “any part of the stock . . . or assets” of another person, of any size.[49] And the Memorandum does not address whether private treble-damages actions under Section 16750 would attach to the new provisions.
Recommendations
In order of priority, we respectfully recommend that the Commission:
- Decline to adopt the “appreciable risk . . . more than a de minimis amount” formulation. If the Commission wishes to clarify “may be,” the staff’s “reasonable probability” alternative is a defensible route, provided it is drafted to govern the assessment of the record as a whole and not paired with codified presumptions.
- Decline to codify the PNB presumption in statutory text, leaving structural inference to case law. At a minimum, replace “evidence clearly showing” with a burden-of-production standard consistent with Baker Hughes, and resolve the conflict between subsections (c) and (e).
- Strike the statutory HHI and market-share thresholds or recast them as triggers for closer scrutiny rather than presumptions of illegality.
- Strike the 2023 Merger Guidelines provision. At most, permit courts to consider contemporaneous federal merger guidelines as nonbinding interpretive aids to the extent consistent with California law.
- Return the “tend to create a monopoly or monopsony” clause to subsection (a) where it operates alongside the substantiality requirement or add a substantiality element to subsection (b).
- Add a size-of-transaction threshold harmonized with SB 25 and the federal HSR thresholds, and specify the remedies and private rights of action, if any, that attach.
- Defer adoption of a substantive merger standard until the Commission has at least one filing cycle of data under SB 25.
Should the Commission nonetheless wish to proceed now, a restrained statute—one tracking Section 7’s operative text, retaining substantiality, keeping both prongs within a single competitive-effects analysis, and leaving market definition, concentration, entry, and efficiencies to case law—would give California courts ample room to reach anticompetitive mergers without the difficulties described above.
We appreciate this opportunity to comment on the draft language, and we would welcome the opportunity to provide further analysis on any of these points.
[1] Geoffrey A. Manne, Dirk Auer, Brian Albrecht & Lazar Radic, ICLE Comments to California Law Revision Commission on Single-Firm Conduct, Int’l Ctr. for L. & Econ. (2025), https://laweconcenter.org/resources/icle-comments-to-california-law-revision-commission-on-single-firm-conduct [hereinafter ICLE SFC Comments].
[2] See, e.g., Geoffrey A. Manne et al., Comments of the International Center for Law & Economics on the FTC & DOJ Draft Merger Guidelines, Docket No. FTC-2023-0043-0001, (Int’l Ctr. for L. & Econ., Sept. 18, 2023), https://laweconcenter.org/wp-content/uploads/2023/09/ICLE-Draft-Merger-Guidelines-Comments-1.pdf [hereinafter ICLE Merger Guidelines Comments]; Ian Adams et al., Comments of the International Center for Law & Economics to the Competition Bureau Canada: Proposed Merger Enforcement Guidelines (Int’l Ctr. for L. & Econ., Feb. 10, 2026), https://laweconcenter.org/wp-content/uploads/2026/02/Competition-Bureau-Canada-Merger-Comments-2026.pdf; Dirk Auer, Selcukhan Ünekbas & Mario A. Zúñiga, Comments of the International Center for Law & Economics: UK Competition and Markets Authority Call for Evidence for Merger Efficiencies Review (Int’l Ctr. for L. & Econ., Feb. 25, 2026), https://laweconcenter.org/wp-content/uploads/2026/02/UK-CMA-Merger-Review-Comments.pdf; Geoffrey A. Manne et al., Comments of the International Center for Law & Economics: EU Draft Merger Guidelines—Public Consultation (Int’l Ctr. for L. & Econ., June 22, 2026), https://laweconcenter.org/wp-content/uploads/2026/06/EU-merger-guidelines-edited.pdf.
[3] Memorandum 2026-29 at 4 (quoting S. Rep. No. 81-1775 at 4298 (1950)) (emphasis omitted).
[4] Brown Shoe Co. v. United States, 370 U.S. 294, 325 (1962); Memorandum 2026-29 at 4–5.
[5] FTC v. Microsoft Corp., 136 F.4th 954, 964 (9th Cir. 2025); Memorandum 2026-29 at 5 n.25.
[6] Saint Alphonsus Med. Ctr.-Nampa Inc. v. St. Luke’s Health Sys., Ltd., 778 F.3d 775, 788 (9th Cir. 2015) (quoting Hospital Corp. of Am. v. FTC, 807 F.2d 1381, 1389 (7th Cir. 1986)); Memorandum 2026-29 at 5 n.26 (citing this passage).
[7] Memorandum 2026-29 at 9 & n.48.
[8] See Press Release, Off. of the Cal. Att’y Gen., Attorney General Bonta Files Lawsuit to Block $110 Billion Warner Bros./Paramount Merger (July 2026), https://oag.ca.gov/news/press-releases/attorney-general-bonta-files-lawsuit-block-110-billion-warner-brosparamount; Press Release, Off. of the Cal. Att’y Gen., Quiet on the Set! Attorney General Bonta Secures Critical, Early Win in Lawsuit to Block Warner Bros./Paramount Merger (July 2026), https://oag.ca.gov/news/press-releases/quiet-set-attorney-general-bonta-secures-critical-early-win-lawsuit-block-warner.
[9] Memorandum 2026-29 at 10; id. at EX 2 (Option Two, subd. (c)). See also United States v. Philadelphia National Bank, 374 U.S. 321 (1963).
[10] United States v. Baker Hughes Inc., 908 F.2d 981, 983 (D.C. Cir. 1990) (Thomas, J., joined by Ginsburg, J.).
[11] Id. at 991.
[12] Id. at 992.
[13] See United States v. General Dynamics Corp., 415 U.S. 486, 503–04 (1974); Baker Hughes, 908 F.2d at 991 (a defendant rebuts by showing “that the prima facie case inaccurately predicts the relevant transaction’s probable effect on future competition”).
[14] Paolo M. Adajar, Ernst R. Berndt & Rena M. Conti, The Surprising Hybrid Pedigree of Measures of Diversity and Economic Concentration (Nat’l Bureau of Econ. Rsch., Working Paper No. 26512, 2019) (abstract); Memorandum 2026-29 at 15 n.78 (quoting the same passage).
[15] John Asker et al., Comments on the January 2022 DOJ and FTC RFI on Merger Enforcement, available at https://www.regulations.gov/comment/FTC-2022-0003-1847, at 15-16.
[16] Memorandum 2026-29 at 14, id. at EX 3–4.
[17] U.S. Dep’t of Justice & Fed. Trade Comm’n, Horizontal Merger Guidelines § 5.3 (2010).
[18] Jay B. Sykes, 2023 Merger Guidelines: Analysis and Issues for Congress, Cong. Rsch. Serv. at 2–3 (Mar. 28, 2024) (quoted in Memorandum 2026-14 at 8–9). See also Carl Shapiro, Evolution of the Merger Guidelines: Is This Fox Too Clever by Half?, 65 Rev. Indus. Org. 147 (2024).
[19] Compare FTC v. Tapestry, Inc., 755 F. Supp. 3d 386 (S.D.N.Y. 2024) (accepting a market for “accessible luxury handbags”), with FTC v. Tempur Sealy Int’l, Inc., 768 F. Supp. 3d 787 (S.D. Tex. 2025) (rejecting a proposed “premium mattresses” market as resting on inconsistent industry usage).
[20] Baker Hughes, 908 F.2d at 992.
[21] Memorandum 2026-29 at EX 3 (Option Three, subd. (e)).
[22] Id.
[23] PNB, 374 U.S. at 370–71.
[24] See FTC v. Meta Platforms, Inc., 775 F. Supp. 3d 16, 69 (D.D.C. 2024).
[25] 2010 Horizontal Merger Guidelines § 10 n.14.
[26] Ohio v. Am. Express Co., 585 U.S. 529 (2018).
[27] Meta Platforms 775 F. Supp 3d at 69.
[28] Daniel Crane, Balancing Effects Across Markets, 80 Antitrust L.J. 397, 397 (2015).
[29] Memorandum 2026-29 at 3–4 & n.19.
[30] See S. Rep. No. 81-1775 at 4 (1950) (“[I]t was not desired that the bill go to the extreme of prohibiting all acquisitions between competing companies.”). As former Assistant Attorney General William Baer put it (also cited in the Memorandum), “[w]ith this revision, Congress declared that lessening competition between the combined firms was not quite the issue. . . .” William J. Baer, Assistant Att’y Gen., Antitrust Div., Dept. of Just., Origins of the Species: The 100 Year Evolution of the Clayton Act, Address at American Bar Association Clayton Act 100th Anniversary Symposium 5 (Dec. 4, 2014) (transcript available at https://www.justice.gov/atr/file/517721/dl).
[31] See Geoffrey A. Manne & Justin (Gus) Hurwitz, Build, Buy, or Both?: On the Antitrust Laws’ Supposed Preference for “Internal Growth” over Acquisitions, 26 Nev. L.J. 53, 69–77 (2025).
[32] S. 225, 117th Cong. (2021), reintroduced as S. 130, 119th Cong. (2025); see Memorandum 2026-29 at 17 n.89.
[33] FTC v. Elders Grain, Inc., 868 F.2d 901, 906 (7th Cir. 1989) (Posner, J.), quoted in Memorandum 2026-29 at 5.
[34] See Cal. Bus. & Prof. Code § 16750(a).
[35] Nat’l Venture Capital Ass’n, NVCA 2021 Yearbook 39-40 (2021), https://nvca.org/wp-content/uploads/2021/03/NVCA-2021-Yearbook.pdf.
[36] See Manne & Hurwitz, supra note 31.
[37] See Memorandum 2025-42 at 6–7 (summarizing the comment of California Life Sciences).
[38] Saint Alphonsus, 778 F.3d at 788; Hospital Corp., 807 F.2d at 1389.
[39] Memorandum 2026-29 at 18.
[40] Id. at 19–20.
[41] Id. at EX 1 (revised purpose statement, subd. (d)).
[42] Id. at 10–11; id. at EX 2–4 (Basic Framework subd. (d); Options Three and Four subd. (f)).
[43] See id. at 7–8 (recounting the 1982 guidelines’ break with the 1968 guidelines); id. at 13–14 (summarizing the California Chamber of Commerce’s objection that earlier editions staked out “dramatically different policy positions”).
[44] Id. at 11(noting “concerns that significant differences in federal and state merger review standards would cause confusion and uncertainty.”)
[45] See, e.g., Memorandum 2026-29 at EX 2 (Option Two, subd. (d)).
[46] ICLE SFC Comments, supra note 1, at 2–3.
[47] See id. (discussing unsettled questions of market definition and measurement in monopsony analysis, particularly in labor markets).
[48] S.B. 25, 2025–2026 Reg. Sess. (Cal. 2026) (California Uniform Antitrust Premerger Notification Act; signed Feb. 10, 2026; operative Jan. 1, 2027).
[49] Memorandum 2026-29 at EX 2 (Option Two, subd. (a)).