California Should Amend the Cartwright Act To Address Single-firm Monopolization



By Kendall MacVey and Wendy Y. Wang1

Unlike Section 2 of the Sherman Act, the Cartwright Act, California’s principal antitrust statute, does not explicitly prohibit monopolization or attempted monopolization.2 Rather, with the exception of one provision prohibiting a condition on purchasers not to use a competitor’s goods or services, the Cartwright Act is silent on monopolization.3

Enacted in 1907, the Cartwright Act made "trusts" unlawful, which are defined as "a combination of capital, skill or acts by two or more persons for" specific purposes.4 California courts at various times have issued decisions that left open whether the Cartwright Act prohibits monopolization.

In 1978, for example, the First Appellate District Court of Appeal in Lowell v. Mother’s Cake & Cookie Co. (1978) 79 Cal.App.3d 13, 23 held that the Cartwright Act prohibits monopolization as the Act "prohibits the combination of resources of two or more independent interests for the purpose of restraining commerce and preventing market competition." But in 1988, the California Supreme Court appeared to disagree, examining the legislative history of the Cartwright Act and concluding that the Legislature did not intend the term "combination" to include mergers.5 Subsequent courts have interpreted that holding to mean that the Cartwright Act does not apply to single-firm monopolization.6 Then in 2015, the California Supreme Court confirmed this interpretation:

We begin with the proposition that agreements to establish or maintain a monopoly are restraints of trade made unlawful by the Cartwright Act. . . . Under general antitrust principles, a business may permissibly develop monopoly power, i.e., "the power to control prices or exclude competition" . . . , through the superiority of its product or business acumen. To acquire or maintain that power through agreement and combination with others, however, is quite a different matter.7

An exception to the Cartwright Act’s exclusion of monopolization has formed insofar as the Cartwright Act does prohibit some monopolies obtained through agreements. An agreement between competitors to not compete or to divide up the territories or customers violates the Cartwright Act, for example.8 But the Act does not appear to apply to

[Page 49]

single-firm monopolization, including when obtained by mergers. In other words, anticompetitive effects from mergers that equal or exceed anticompetitive effects resulting from agreements among competitors are not currently addressed by the Cartwright Act.

Citing growing concerns over lack of competition, concentration of market power, and problematic monopolies, the California Legislature adopted Assembly Concurrent Resolution No. 95 in 2022 and approved the California Law Revision Commission to study, among other things, whether California law should be revised to outlaw single-firm monopolization.9

As California is poised to overtake Germany as the fourth largest economy in the world,10California needs its own law to address single-firm monopolization and catch up with the times. This article will examine the legislative history of the Cartwright Act and relevant caselaw, earlier legislative attempts to prohibit conducts and agreements leading to monopolies, the growing concerns over monopolies, the need for California to address monopolization, New York State’s "Twenty-First Century Anti-Trust Act" and the "Competition and Antitrust Law Enforcement Reform Act of 2021" introduced in the United States Senate.


California’s antitrust laws differ from federal antitrust laws in that the Cartwright Act does not prohibit single-firm monopolization or attempted monopolization. Prior to 1988, numerous California courts, including the California Supreme Court, repeatedly held that the Cartwright Act "is patterned upon the federal Sherman Act" and "federal cases interpreting the Sherman Act are applicable with respect to the Cartwright Act."11The First Appellate District Court of Appeal even held that: "[t]hough not specifically listed [in the Cartwright Act], monopoly is a prohibited restraint of trade."12

However, in 1988, the California Supreme Court re-examined the legislative history of the Cartwright Act and concluded that the Act was not derived from the Sherman Act, but rather from other state laws.13In State of California ex rel. Van de Kamp v. Texaco, Inc. (Texaco) the California Attorney General sued under the Cartwright Act and the Unfair Practices Act to enjoin defendant Texaco, Inc., from acquiring California assets of Getty Oil Company (Getty) pursuant to a merger/acquisition agreement between the two companies.14 Texaco entered into a consent order with the Federal Trade Commission (FTC) in July 10, 1984 wherein Texaco agreed to divest designated assets.15 However, the California Attorney General was unsatisfied with the consent order and asserted that the merger might substantially lessen competition in the state market.16

The Attorney General contended that the Cartwright Act applied to mergers as a merger is a "combination of capital."17 Defendants asserted that the word "combination" applies only to a situation in which separate and independent entities act in concert for a certain purpose and thereafter continue to maintain their separate identities and interests. Thus, a merger would not be a combination, because post-merger, the two merged entities would no longer maintain separate identities and interests.18

To help it interpret the statutory intent behind the word "combination," the California Supreme Court examined state and federal statutes and the body of caselaw interpreting those statutes when the Cartwright Act was adopted.19

The court then concluded that the Cartwright Act was patterned after an alternative bill to what ultimately became the Sherman Act.20 Both bills were introduced to the U.S. Senate in 1888, and in the two years that the competing bills were pending in the Senate, several states enacted their own antitrust laws.21 These new state antitrust laws generally fell into two categories: (1) the Kansas-Maine format, which made illegal "all arrangements, contracts, agreements, trusts or combinations" for certain improper purposes22; and (2) the Texas-Michigan format, which declared "trusts" illegal

[Page 50]

and defined "trust" as a "combination of capital, skill or acts" for certain purposes.23 Following the enactment of those state laws, many courts interpreted the term "combination" as not applying to a merger of two companies.24 In response to this narrow interpretation of "combination," some states subsequently amended their antitrust laws to specifically address monopolies and mergers.25

The Cartwright Act was patterned after the Texas-Michigan format, which was modeled after a failed U.S. Senate Bill introduced in 1888 as an alternative to the eventually adopted Sherman Act. By the time California enacted the Cartwright Act in 1907, there was already a body of caselaw providing a narrow interpretation of "combination," but the California Legislature chose to pattern the state’s antitrust laws on the original Texas-Michigan format without incorporating any subsequent anti-monopolization or anti-merger provisions that were adopted by other state legislatures, including Texas, prior to 1907.26 Based on this history, the California Supreme Court concluded that, in adopting the Cartwright Act, the Legislature must have intended the prohibited trust to be "combination" by two separate, independent entities.27

While Texaco concerned a merger-not monopolization-subsequent courts have interpreted Texaco as holding that the Cartwright Act does not apply to single-firm monopolization.28 Although conspiracies or agreements to establish or maintain a monopoly through "combinations" remains unlawful in California,29 the reality is that the California Legislature has never incorporated language similar to Section 2 of the Sherman Act into the Cartwright Act. Until the Legislature makes it clear that it intends to prohibit monopolization or attempted monopolization, actions under the Cartwright Act against such conduct may be successful only if the defendants also run afoul of explicit provisions of the Act by engaging in a prohibited combination, such as engaging in "a horizontal allocation of markets with would-be competitors [by] dividing up territories or customers," or paying "its only potential competitor not to compete in return for a share of the profits that firm can obtain by being a monopolist."30


Following Texaco, the California Legislature considered at least three separate proposals to prohibit single-firm monopolization, but none of these proposals were enacted. Assembly Bill 671 (AB671), introduced in February 1989, would have forbidden "any person to monopolize, or attempt to monopolize, or to combine or conspire with any person to monopolize any part of trade or commerce."31 This bill would have also permitted the California courts to divest assets acquired in a merger.32 California Assembly approved this bill by a vote of 46 to 29. The bill was subsequently referred to the Senate Judiciary Committee, and despite four amendments the bill failed to garner enough votes to proceed out of committee.33 According to a subsequent legislative analysis on a related bill, while the anti-monopoly provision in AB671 was not controversial, there were significant opposition to the merger and divestiture provisions.34

In February 2002, a bill was introduced in the Senate by State Senator Joseph Dunn to prohibit single-firm monopolization or attempted monopolization.35While the Senate passed this bill by a vote of 21 to 15, the Assembly did not adopt it.36 Opponents to the bill were against "the state prohibition on monopoly," thought the bill "would run counter to an established U.S. Supreme Court decision, [and would] make California law different from federal law" because California law permits indirect purchaser lawsuits and this bill would allow such purchasers to bring actions for monopoly, and would "increase liability and litigation for businesses."37

State Senator Dunn introduced SB 1274 in 2006 to again prohibit monopolization in California.38SB 1274 defines the term "monopolize" to include "monopsonize."39 This time the Senate rejected the bill by a vote of 14 to 19.40

These repeated failed proposals booster claims that the California Legislature does not intend to forbid single-firm monopolization.

[Page 51]


Since the 2007-2008 global financial crisis and subsequent series of financial scandals, there has been increasing concern about market concentration and anticompetitive conduct.41 Even some aligned with the heritage of George Stigler, one of the key founders of the "Chicago School" on industrial organization economics, have raised concerns that market concentration and monopolization are becoming more problematic in the American economy.42 This is a significant shift given the Chicago School’s policy tradition of a hands-off approach toward antitrust enforcement that has been a dominant force in antitrust policy circles since the 1970s. This change in attitude in part may be attributed to the growing perception of inadequate antitrust enforcement in the face of changing market conditions in major industries.43

According to The Economist, two-thirds of the country’s approximately 900 industries have become more concentrated since the 1990s.44 "In regulated industries that don’t face competition from imports—health care, airlines and telecommunications—prices are at least 50% higher than in other rich countries, and returns on capital are high."45

The technology industry in particular has been receiving a lot of attention and scrutiny. The big five platform technology companies (Alphabet, Amazon, Apple, Facebook, and Microsoft) have collectively purchased over 500 firms-often smaller competitors, have gathered customer data that could lock those customers into their products, and have exerted their market power vertically through the supply chain.46 Luigi Zingales, head of the University of Chicago’s George J. Stigler Center for the Study of the Economy and the State, expressed concerns that today’s large technology companies are "unprecedented in nature" and that existing antitrust laws may be insufficient to address monopolization in technology companies.47

The increasing public perception of large technology companies wielding monopolistic power has not always translated to successful prosecution of perceived monopolization in the courtrooms. In September 2021, the District Court of the Northern District of California rejected Epic Game’s allegations that Apple was engaging in an illegal monopoly, despite also finding that Apple had violated California’s Unfair Competition Law by forcing developers into using Apple’s payment processing service and forbidding developers from communicating lower prices on other platforms.48This failure to prosecute perceived monopolization, as well as other anticompetitive conducts and perceived procedural setbacks in antitrust lawsuits,49 have contributed to the opinion that existing antitrust laws are insufficient or inadequate to address tech monopolies.50

Noting the inadequacy of existing laws in face of changing business landscape, some federal and state legislators have proposed bills to address those inadequacies. In 2021, both the U.S. House and the Senate introduced bills to update the federal antitrust statutes, and New York state senators also proposed new legislation to, among other things, prohibit monopsony and permit class action antitrust lawsuits.51 None of these measures was adopted, but they are explicitly listed in California’s Assembly Concurrent Resolution No. 95 as potential templates for California’s own reform of its antitrust laws. As discussed below, these federal and state proposals have helpful language that California can incorporate, but the California Legislature first must decide it will prohibit single-firm monopolizations.


Earlier this year, California joined seven other states and the U.S. Department of Justice in a lawsuit charging Google with operating an unfair monopolizing scheme in markets for advertising technology.52 In a statement regarding the lawsuit, California Attorney General Rob Bonta commented, "Poised to become the fourth largest economy in the

[Page 52]

world, it is in California’s best interest to ensure that creativity, innovation, and competition in technology are protected."53 This lawsuit is one of the many efforts by the Attorney General in recent years to curtail anticompetitive behaviors in the technology industries by Facebook, Amazon, and Google.54

None of these efforts by the California Attorney General to curtail anticompetitive behaviors was based on a unilateral monopolization theory under the Cartwright Act. The lawsuit against Google was for violation of the Sherman Act.55 The lawsuit against Amazon, brought in California state court in 2022, challenges Amazon’s agreement with merchants that penalizes merchants if they offer products for a lower price off-Amazon, which California alleges is a violation of the Unfair Competition Law and the Cartwright Act.56 These lawsuits highlight California’s interest in prosecuting anticompetitive acts by large technology companies and the limits of the state’s existing antitrust laws-namely, it primarily relies on the Sherman Act and federal enforcement to prosecute single-firm monopolization.

As the home of Silicon Valley where many technology companies are headquartered, some may argue California has an interest to ensure that firms with market power in California markets do not stifle competition and innovation, and ultimately increase prices for consumers. In other words, California is the home to many unique industries that the state has an economic interest in keeping competitive both for the sake of its economy and its constituents. But there are also other local geographic and product markets in California, perhaps not as glamorous or attention-getting. If any such local markets face the threat or actuality of single-firm monopolization, there is no tool under state law to remedy the situation. Even if single-firm conduct has much greater anticompetitive impacts than "combinations" that are already prohibited by the Cartwright Act, nothing can be done about these impacts under state law. This is a gaping hole that cannot be assumed will ever be filled in by discretionary federal antitrust enforcement or litigation under the Sherman Act or other federal antitrust statutes.57

California has been on the forefront of ensuring a pro-competitive legal structure with respect to employment and professional mobility. Specifically, Section 16600 of the California Business & Professions Code, with certain limited exceptions, prohibits contracts that restrain a person from engaging in any lawful profession, trade or business. Many attribute the formation of the Silicon Valley in California to this pro-competition law that is able to draw talent to California and promote competition for talent.58 After creating one of the most pro-competition environments that permitted innovation in technology to flourish and develop into Silicon Valley, California should now catch up with the Sherman Act of 1890.

The courts have written out of the Cartwright Act any prohibition or remedy to address single-firm monopolization in California. Instead, the Cartwright Act is now limited to addressing combinations between existing firms. But if a single firm does monopolize a relevant market in California-thereby raising prices, stifling innovation, and reducing output-consumers, businesses and public entities have no remedy under state law to recover damages in state court no matter the magnitude of the injury.

Perhaps more remarkable is that currently, under the Cartwright Act, if a group of firms combine to form a single-firm monopoly in California at the expense of California consumers and businesses, little to nothing can be done under state law in state courts to recover damages. The legal rationale for this outcome is that the Cartwright Act only concerns combinations, and once there is only a post-combination single firm, there can be no combination. It is difficult to explain why a combination of firms that results in total monopolization by a single firm should be rewarded with antitrust immunity. Rather, this appears to be a situation that demands antitrust action, not antitrust nullification.59

[Page 53]

It is also ultimately inexplicable why it makes sense for Californians to be able to use the Cartwright Act to address local price fixing and other cartel-type anticompetitive conduct but are to be barred from addressing equally harmful anticompetitive conduct by a single firm.

Nor can it be assumed that the federal antitrust laws, such as the Sherman Act, will fill this gap under the Cartwright Act. Markets and market injuries can be specifically, uniquely or entirely local. Federal antitrust law enforcers cannot be counted on in having the same interests and incentives to go after local problems that local consumers, businesses, and public entities have. Nor can it be assumed that federal courts automatically will have jurisdiction to address such local concerns.

What is the solution? The California Legislature should amend the Cartwright Act to prohibit single-firm monopolization or attempts to monopolize by reciting parallel language from Section 2 of the Sherman Act concerning monopolization. Adopting the language from Section 2 has the benefit of being able to use established caselaw concerning the interpretation of the Sherman Act to the amended Cartwright Act as an instructive guide. Such an amendment would fill a gaping hole in the Cartwright Act without opening up the prospect of an unpredictable body of law. In short, Sherman Act caselaw can provide guidance in addressing single-firm monopolization in local, California markets just as the Sherman Act continues to provide guidance in dealing with conduct such as horizontal price fixing and market divisions.


In authorizing the California Law Revision Commission to study whether to amend the Cartwright Act, the California Legislature specifically directed the Commission to review New York’s proposed "Twenty-First Century Anti-Trust Act" and the "Competition and Antitrust Law Enforcement Reform Act of 2021" introduced in the U.S. Senate. Both the New York and federal bills go beyond merely prohibiting single-firm monopolization, and would make it easier to prosecute antitrust claims. While the California Legislature may consider adopting similar provisions in those bills, their failure to be adopted by the New York Assembly and U.S. Senate likely signals that reducing costs of prosecuting antitrust lawsuits or lowering the legal standard for what unlawful monopolization is remain controversial. Saddling a straight-forward bill prohibiting monopolization or monopsonization with these other provisions may make it more difficult for the California Legislature to amend the Cartwright Act.


New York’s existing antitrust statute, known as the Donnelly Act, already prohibits contracts, agreements, arrangements, or combinations that establish or maintain a monopoly that restrains competition.60 However, that statute, as it currently exists, suffers from the same constraint the Cartwright Act does in that it does not prohibit single entity monopoly from engaging in anticompetitive acts.61

Citing the need to "combat cartels, monopolies, and other anti-competitive business practices" and finding that "unilateral actions which seek to create a monopoly or monopsony are as harmful as contracts or agreements of multiple parties to do the same," several New York state senators introduced Senate Bill 933C to amend the Donnelly Act in January 2021.62 SB 933C would have prohibited anticompetitive monopsonizing as well as monopolizing behaviors.63 SB 933C also would make it unlawful for any person(s) "with a dominant position . . . to abuse that dominant position."64The bill set forth examples of direct and indirect evidence that can establish a "dominant position," including the unilateral power to set prices, terms, or conditions (direct evidence), or market share (indirect evidence). If a seller has a forty percent or greater share of a relevant market, the bill presumes

[Page 54]

that the seller has a dominant position. The percentage drops to thirty percent for a buyer. The bill also eliminates the need to establish a relevant market if the dominant position is established by direct evidence. The bill also requires any company conducting business in New York that is subject to the reporting requirements of the Hart-Scott-Rodino Antitrust Improvements Act of 1976 to provide the same notice at the same time with the New York Attorney General.65

SB 933C also would have made it less cost prohibitive for private parties to prosecute antitrust claims. Specifically, it permitted class actions for damages recovery, and recovery of expert witnesses and consultants’ fees and costs incurred by both the attorney general and private litigants if they prevailed in the lawsuit.66

Although New York Senate passed SB 933C, the bill died in Assembly in January 2022.67 The New York Senate amended and passed the bill again in May 2022. The bill was referred to Assembly Committee on Economic Development. No floor vote was taken by the Assembly before the 2021-2022 legislative session ended.68


Having stated that the United States has "a major monopoly problem" and identifying technology and pharmaceutical industries as the ones with the biggest antitrust problems, U.S. Senator Amy Klobuchar introduced U.S. Senate Bill 225, known as the "Competition and Antitrust Law Enforcement Reform Act of 2021" on February 4, 2021.69 The bill proposed many changes to the existing law, including lowering the legal standard for finding a merger or acquisition unlawful from "where the effect of the acquisition may be substantially to lessen competition" to "where the effect of the acquisition may be to create an appreciable risk of materially lessening." The bill would have also amended Section 7 of the Clayton Act to make mergers tending to create a monopsony unlawful to the same extent a monopoly would. For cases brought by the U.S. Department of Justice, FTC, or state attorneys general, courts "shall" determine that the legal standard for finding a merger or acquisition unlawful has been met if certain conditions are met, such as if the acquiring person has a market share of greater than fifty percent and the acquiring person has a reasonable probability of competing with the entities or assets it would control as a result of the acquisition. The bill also prohibited companies from engaging in "exclusionary conduct that presents an appreciable risk of harming competition." An appreciable risk is presumed if at least one party engaging in the exclusionary conduct has "significant market power" or over fifty percent of the market share. The bill also would have significantly increased monetary penalties for antitrust violations.70

Ultimately, the U.S. Senate did not vote on this bill. Senator Klobuchar has yet to introduce a similar bill in the new Congressional session.


To protect competition within California and to promote innovations, California should amend the Cartwright Act to address single-firm conduct in a manner similar to Section 2 of the Sherman Act. Doing so will allow courts to rely on existing caselaw interpreting the Sherman Act in enforcing California’s antitrust laws. However, as many lawmakers have pointed out, prosecuting antitrust cases against Big Tech companies under existing laws have proven to be challenging. Both the New York bill and the Competition and Antitrust Law Enforcement Reform Act sought to lower the threshold to prosecute unlawful monopoly and monopsony. The California Legislature may wish to consider updating the Cartwright Act with similar provisions proposed in the U.S. Senate and the New York Legislature. However, those bills were ultimately not adopted by Congress or the New York Assembly and combining the controversial provisions in those bills with a legislation prohibiting single-firm monopolization may make it more difficult for such bill to be adopted.

[Page 55]

While recent press coverage has focused on Big Tech and large national companies, the California Legislature should not lose sight of monopolization in regional, geographic markets that are unique to California and might not receive national attention or otherwise be addressed by federal antitrust enforcement in federal courts. As California is poised to overtake Germany as the fourth largest economy in the world,71 California needs its own law to address single-firm monopolization and catch up with the times.



1. Kendall MacVey is a partner and litigator with Best Best & Krieger LLP and also a professor of practice at the University of California Riverside School of Public Policy. He has served as chair of the Antitrust Section of the Los Angeles County Bar Association and as an attorney for the Federal Trade Commission where he did antitrust enforcement. Wendy Y. Wang is of counsel with Best Best & Krieger LLP and focuses on complex litigation. The views expressed herein are solely those of the authors, who are responsible for the content, and do not necessarily represent the views of Best Best & Krieger LLP or any institution.

2. Section 2 of the Sherman Act provides: "Every person who shall monopolize, or attempt to monopolize, or combine or conspire with any other person or persons, to monopolize any part of the trade or commerce among the several States, or with foreign nations, shall be deemed guilty of a felony . . . ." 15 U.S.C. § 2.

3. See Cal. Bus. & Prof. Code, § 16727 ("It shall be unlawful for any person to lease or make a sale or contract for the sale of goods, merchandise, machinery, supplies, commodities for use within the State, or to fix a price charged therefor, or discount from, or rebate upon, such price, on the condition, agreement or understanding that the lessee or purchaser thereof shall not use or deal in the goods, merchandise, machinery, supplies, commodities, or services of a competitor or competitors of the lessor or seller, where the effect of such lease, sale, or contract for sale or such condition, agreement or understanding may be to substantially lessen competition or tend to create a monopoly in any line of trade or commerce in any section of the State.") (emphasis added)).

4. Id. §§ 16720 & 16726.

5. State of California ex rel. Van de Kamp v. Texaco, Inc. 46 Cal.3d 1147, 1162-1163 (1988).

6. Asahi Kasei Pharma Corp. v. CoTherix, Inc. 204 Cal. App.4th 1, 8 (2012) ("The Cartwright Act bans combinations, but single firm monopolization is not cognizable under the Cartwright Act."); Freeman v. San Diego Ass’n of Realtors 77 Cal.App.4th 171, 202 (1999) (Texaco decided "that the Cartwright Act bans combinations but does not have any provisions parallel to Sherman Act section 2’s anti-monopoly provisions.").

7. In re Cipro Cases I & II 61 Cal.4th 116, 148 (2015) (citations omitted).

8. Id.

9. Assem. Con. No. 95, 2021-22 Reg. Sess. (Cal. 2021).

10. Matthew A. Winkler, California Poised to Overtake Germany as World’s No. 4 Economy, Bloomberg (Oct. 24, 2022),

11. Chicago Title Ins. Co. v. Great W. Fin. Corp. 69 Cal.2d 305, 315 (1968); see also, Marin Cnty. Bd. of Realtors, Inc. v. Palsson 16 Cal.3d 920, 925 (1976) ("A long line of California cases has concluded that the Cartwright Act is patterned after the Sherman Act and both statutes have their roots in the common law. Consequently, federal cases interpreting the Sherman Act are applicable to problems arising under the Cartwright Act."); R. E. Spriggs Co. v. Adolph Coors Co. 37 Cal.App.3d 653, 659, fn. 5 (1974); Sherman v. Mertz Enters., 42 Cal. App.3d 769, 775-776 (1974).

12. Lowell v. Mother’s Cake & Cookie Co. 79 Cal.App.3d 13, 23 (1978).

13. State of California ex rel. Van de Kamp v. Texaco, Inc. 46 Cal.3d 1147, 1164 (1988) (Texaco).

14. Id. at 1150-51.

15. Id. at pp. 1151-1152.

16. Id. at p. 1152.

17. Id. at pp. 1152-53; Cal. Bus. & Prof. Code, § 16720.

18. Texaco, 46 Cal. 3d at pp. 1152-53.

19. Id. at 1153-62.

20. Id. at 1153.

21. Id.

22. Id.

23. Id.

24. Id. at 1159.

25. Id. at 1159-60.

26. Id. at 1159-62.

27. Id. at 1162-63. It is worth noting that it appears counsel for Texaco sought an extension of the briefing schedule before the California Supreme Court because Hons. Rose Bird, Joseph Grodin, and Cruz Reynoso as California Supreme Court justices were facing a recall and Texaco counsel were hoping for a change in the line-up of justices. As a result of the recall, the make-up of the Court did change when the Texaco decision was ultimately issued by the Court. See Sec. 1.02(b) fn. 113, Calif. Lawyers Association, California Antitrust and Unfair Competition Law (Revised Edition 2022).

28. Asahi Kasei Pharma Corp. v. CoTherix, Inc. 204 Cal. App.4th 1, 8 (2012) ("The Cartwright Act bans combinations, but single firm monopolization is not cognizable under the Cartwright Act."); Freeman v. San Diego Ass’n of Realtors 77 Cal.App.4th 171, 202 (1999) (Texaco decided "that the Cartwright Act bans combinations but does not have any provisions parallel to Sherman Act section 2’s anti-monopoly provisions.").

29. In re Cipro Cases I & II 61 Cal.4th 116, 148 (2015).

30. Id.

31. Assem. 671, 1989-90 Reg. Sess. (Cal. 1989) (as introduced Feb. 1989).

32. Id.

33. Assembly Final History, 1989-90 Leg. Reg. Sess. And 1989-90 First Extra. Sess., Vol. 1, at p. 541, available at

34. Assembly Committee on Business and Professions Analysis for 6/25/02 hearing on S.B. 1814, at p. 7, available at

35. S. 1814, 2001-02 Reg. Sess. (Cal. 2002) (as introduced Feb. 2002).

36. Legislative history available at

37. Assembly Committee on Business and Professions Analysis for 6/25/02 hearing on S.B. 1814, at p. 6, available at

38. S. 1274, 2005-06 Reg. Sess. (Cal. 2006) (as amended April 4, 2006).

39. Id.

40. Legislative history available at:

41. See Adena Friedman, Ideas for Modernizing Capitalism, The World in 2020, The Economist (Last visited June 24, 2023); Alistair Gray. Top Financier Warns on Anti-Business Sentiment, Financial Times (Sept. 29, 2015),

42. Daisuke Wakabayashi, A Challenge to Big Tech and Antitrust Thinking in a Surprising Place, N.Y. Times, (Sept. 15, 2019),; Schumpeter: Crony capitalism: Bright minds in Chicago worry about the state of competition in America, The Economist (Apr. 15, 2017). See generally antitrust articles at the Stigler Center’s website, available at

43. See The Economist, supra note 42. See also G. Grullon et al., Are US Industries Becoming More Concentrated?, 23(4) Rev. Fin. 697 (2019),

44. See The Economist, supra note 42.

45. Id. Several economic studies utilizing different measures of concentration have found increasing concentration in the US to be associated with higher mark-ups, corporate profits, and reduced entry with potential negative effects to consumer welfare. See, e.g., De Loeacker, J. Eeckhout, S. Mongey "Quantifying Market Power and Business Dynamics in the Macroeconomy," (May 2021); National Bureau of Economic Research Working Paper 28761 available at; Council of Economic Advisers Issue Brief April 2016, "Benefits of Competition and Indicators of Market Power." For a thorough but less technical review by an economist who has conducted a number of studies on market concentration trends and their negative effects on consumers see T. Philippon, The Great Reversal—How America Gave Up on Free Markets (Harvard University Press 2019).

46. Id.

47. See Wakabayashi, supra note 42.

48. Rule 52 Order After Trial On The Merits, Epic Games, Inc. v. Apple Inc., No. 4:20-cv-05640-YGR, (N.D. Cal. Sept. 10, 2021),

49. Cat Zakrzewski, Rulings in Facebook, Apple Antitrust Cases Show How Tough It Is to Define a Monopoly in the Age of Big Tech, Wash. Post, (Sept. 10, 2021),; FTC v. Facebook, Inc., 560 F. Supp. 3d 1, (D.D.C. 2021),

50. See Zakrzewski, supra note 49.

51. Id.; S. 225, 117th Cong. (2021) (as introduced on February 4, 2021); S. 933C, 2021-22 Leg. Sess. (NY 2021) (as introduced on January 6, 2021).

52. Leah Nylen, U.S. Sues Google, Calls for Breakup of Ad Technology ‘Monopoly’, L.A. Times, Jan. 24, 2023.

53. Press Release, Cal. Dep’t of Just., "Attorney General Bonta Files Lawsuit Against Google for Monopolization of Ad Tech Markets," Jan. 24, 2023.

54. Id.

55. Complaint, ¶305, United States of America v. Google LLC, No. 1:23-cv-00108, (E.D. Va. Jan. 24, 2023), ("Plaintiffs California, Colorado, Connecticut, New Jersey, New York, Rhode Island, Tennessee, and Virginia by and through their respective Attorneys General, bring this action pursuant to Section 16 of the Clayton Act, 15 U.S.C. § 26, to prevent and restrain Google’s violations of Sections 1 and 2 of the Sherman Act, 15 U.S.C. §§ 1, 2.")

56. See generally, Complaint, California v., Inc., No. CGC-22-601826 (Cal. Super. Ct. Sept. 15, 2022) ,; Order on Amazon’s Demurrer to the Complaint, California v., Inc., No. CGC-22-601826 (Cal. Super. Ct. Mar. 30, 2023),

57. See The Economist, supra note 42 ("Over time the Chicago school’s ideas became so influential that the courts and the two antitrust regulators, the Department of Justice (DoJ) and the Federal Trade Commission (FTC), adopted a far more favorable approach to big business."); See generally E. Thomas Sullivan, The Antitrust Division as a Regulatory Agency: An Enforcement Policy in Transition, 64 Wash. U. L.Q. 997, 998 (1986) (the Reagan administration eased antitrust standards)

58. Larry Downes, How Europe Can Create Its Own Silicon Valley, Harv. Bus. Rev. (June 11, 2015),

59. It should be noted that a "single firm" can include parents and subsidiaries. It has been held that a corporation and subsidiaries it controls cannot conspire with each other. See, e.g., In re Auto Antitrust Cases I & II, 1 Cal. App. 5th, 155 (2016), citing Copperweld Corp. v. Indep. Tube Corp., 467 U.S. 752. 769-71 (1984).

60. N.Y. Gen. Bus. Law § 340.

61. Commonwealth Elec. Inspection Servs., Inc. v. Town of Clarence, 6 A.D.3d 1185, 1186 (N.Y. 2004) ("We note that the statutory term ‘arrangement,’ like the statutory terms ‘contract,’ ‘agreement,’ and ‘combination,’ refers to bilateral conduct and does not connote ‘a one-sided practice’").

62. S. 933C, 2021-22 Leg. Sess. (NY 2021) (as introduced on January 6, 2021).

63. Id.

64. Id.

65. Id.

66. Id.


68. Id. This bill does not appear to have been reintroduced in the 2023-2024 session.

69. S. 225, 117th Cong. (2021) (as introduced on February 4, 2021); Brian Fung, Sen. Amy Klobuchar: ‘We have a major monopoly problem’, The Washington Post, March 5, 2019, available at

70. S. 225, 117th Congress 1st Session (U.S. Senate 2021) (as introduced on February 4, 2021).

71. See Winkler, supra note 10.

[Page 56]