In late May, the New York Times ran a story by Eric Lipton titled “Elon Musk Dominates Space Launch. Rivals Are Calling Foul.” In response, the antitrust community largely shrugged its shoulders. I went back and give it a read, along with related stories in the Wall Street Journal (“Elon Musk’s SpaceX Now Has a ‘De Facto’ Monopoly on Rocket Launches”), the Washington Post (“SpaceX could finally face competition. It may be too late.”), and CNBC (“SpaceX’s near monopoly on rocket launches is a ‘huge concern,’ Lazard banker warns”). Having reviewed the theories of competitive harm and the publicly available evidence, I conclude that there is a monopolization case worth pursuing here.

Lipton’s piece in the Times contained two noteworthy allegations (emphasis added):

Jim Cantrell worked with Mr. Musk at the founding of SpaceX in 2002. When he started to build his own launch company, Phantom Space, two potential customers told his sales team they could not sign deals because SpaceX inserts provisions in its contracts to discourage customers from using rivals.

Peter Beck, an aerospace engineer from New Zealand, met in 2019 with Mr. Musk to talk about Mr. Beck’s own launch company, called Rocket Lab. Several months later, SpaceX moved to start carrying small payloads at a discounted price that Mr. Beck and other industry executives said was intended to undercut their chances of success.

The first allegation refers to what economists consider an exclusionary contract: You can buy from me only if you commit to not buying from my rival. Other exclusionary provisions include demanding that buyers fulfill a large portion of their needs with the seller or that buyers give the seller a right to match. The second allegation sounds like predation, which requires pricing below a firm’s incremental costs and a likely chance of recoupment. Both are well-recognized restraints of trade that can generate anticompetitive effects under certain conditions, the first of which is when the restraint is employed by a dominant firm.

SpaceX is dominant in space transportation

Firms that are not dominant in a market can engage in exclusionary tactics without fear of exposing themselves to antitrust scrutiny. It is the combination of market power plus an exclusionary restraint that generates anticompetitive effects. Obtaining market shares on a privately held company like SpaceX, is admittedly difficult. But the New York Times story tell us that in 2023, “SpaceX secured $3.1 billion in federal prime contracts, according to the data, nearly as much as the combined amount the federal government committed for space transportation and related services from its nine competitors, from giants like Boeing and Northrop Grumman to startups like Blue Origin.” This statistic implies that, at least as a share of government spending for space transportation, SpaceX commands nearly a 50 percent share. The article also tell us that “SpaceX’s 96 successful orbital launches during 2023 contrast with seven launches to orbit from the U.S. in total last year by all of SpaceX’s competitors,” indicating a share of over 93 percent when measured in terms of launches. In the same story, Musk himself reckons that as of 2023, SpaceX delivered 80 percent of the world’s cargo to space. According to BryceTech, in the fourth quarter of 2023, SpaceX lifted nearly 90 percent of all pounds sent into orbit. Any share in this range (50 to 93 percent) would be consistent with dominance, particularly when combined with evidence of entry barriers.

SpaceX’s market share is protected by entry barriers

By the time SpaceX launched its 63rd mission of 2023, ULA, the next largest U.S. rocket competitor, had completed just two launches. Each rocket launch leads to new data, the same way that each drive by a Tesla owner gave Tesla new information over its electric vehicle rivals. (A similar incumbency advantage owing to learning economies prompted policymakers to endorse subsidizing charging stations and even forcing Tesla to open its stations to EV rivals.) The Washington Post story has a line from the CEO of Firefly Aerospace that supports this effect: “You could see a scenario where one provider has such a lead … that it is literally impossible to catch up on the order where there will be true competition.” Moreover, SpaceX has “deep ties to NASA and the Pentagon, which have awarded it billions of dollars in contracts and elevated it to prime contractor status.”

There are myriad other natural barriers to entry:

• High fixed costs: Lars Hoffman, then senior vice president at Rocket Lab, estimated in 2020 that it cost $100 million to get a rocket to its first launch;
• Long development periods: Development periods of at least three to five years for rockets are common. Blue Origin’s first orbital launch is more than three years behind schedule and now planned for later this year; and
• Strategic launch schedules: According to the Wall Street Journal, “SpaceX’s grip on the launch business means many government agencies and satellite operators must tether their ambitions to the company’s timetables and capabilities.” Per the Washington Post, “SpaceX’s perch atop the industry has allowed it to dictate timelines and prices for satellite launches that favor its launch cadence and schedule, industry officials said.”

In an attempt at journalistic balance, Lipton suggests that competitive entry is picking up despite these natural impediments:

Jeff Bezos’ Blue Origin is close to its first launch for its New Glenn rocket. RocketLab is building what it calls Neutron, and Relativity Space is working on its TerranR, among other new entrants. After years of delays, Boeing is soon expected to start launching NASA astronauts into space on its new Starliner spacecraft.

Lipton ultimately concludes, however, that the ability of the United States to reach orbit in the near term “remains largely dependent on Mr. Musk and his Falcon 9 rocket.” The aforementioned high fixed costs, long development periods, and strategic launch schedules can counter any evidence of initial entry. Even if these natural barriers could be overcome, entrants would still have to hurdle the artificial barriers erected by SpaceX’s two forms of exclusionary conduct.

SpaceX’s ride-sharing program might be predatory

Recall that Mr. Beck of Rocket Lab alleged that SpaceX started carrying small payloads at a discounted price that Rocket Lab could not match. Here’s more on the predation allegation from the New York Times:

[Beck] and other industry executives said they were convinced that SpaceX had set the price for its Transporter service — where small satellite companies can book slots on a Falcon 9 launch — with the explicit goal of undermining the financial plans of emerging competitors. Transporter’s low price — initially $5,000 per kilogram — was below what some industry executives calculated was SpaceX’s basic cost. They concluded that SpaceX could only offer such a low price by subsiding those flights with some of its government contracting revenue.

Beck also asserted that SpaceX was selling flights on its new Bandwagon service, which offers satellite makers launches to orbits that provide them better coverage over key sections of the world, “far below its own costs to undermine its competition.”

To know whether such pricing is in fact predatory, one must estimate the incremental (that is, avoidable) cost for SpaceX’s ride-sharing missions. Adding one payload to a rocket likely imposes no incremental costs for SpaceX. Thus, the test should be performed on a per launch basis.

The best estimate of SpaceX’s marginal costs per launch comes from Musk himself at $15 million under a “best-case” scenario. But that number excludes other avoidable costs, including “the costs to refurbish the first stage rocket booster, and the cost to recover and refurbish fairings.” Musk also claims that, with regard to manufacturing costs, SpaceX incurs “$10 million to manufacture a new upper stage [rocket] and that this stage represents about 20 percent of the cost of developing the rocket.” If SpaceX replaces this upper-stage rocket every mission, then the incremental costs are $25 million.

Turning to the revenue side of the equation, SpaceX’s average incremental revenue per launch has declined to roughly $22.5 million (equal to $300k per payload times the average of 75 payloads per launch). This would not cover the incremental costs estimated above, and to the extent these numbers are accurate, would be predatory. Of course, these estimates are based on publicly available information. An antitrust agency pursuing an investigation would be able to obtain more precise estimates.

I also find the evidence on the likelihood of recoupment to be highly persuasive. The Washington Post story offers this line on ride-sharing: “One example of how SpaceX made it tough on competitors was its move a few years ago to launch smaller satellites in bunches at very low prices in a ‘rideshare program’ that was seen in the industry as a tactic to target smaller launch companies such as Rocket Lab by taking away customers.” The aforementioned evidence of the high fixed costs and long development periods also make recoupment more likely. Finally, the rocket industry is subject to considerable scale economies, so any practice that denies rivals the ability to achieve scale could be seen as exclusionary and consistent with the classic raising-rivals’-cost framework.

SpaceX’s contracts with customers seem to be exclusionary

The second potentially anticompetitive restraint employed by SpaceX is exclusionary provisions in contracts with its customers, comprised largely of government agencies and satellite companies (many of whom compete against Starlink). Here is a little more detail from the New York Times on SpaceX’s contracting:

Mr. Cantrell, whose company Phantom Space has received funding from NASA to help build its new launch vehicle, said his sales team had been told by Sidus Space and a second company that SpaceX had demanded contract provisions intended to limit their ability to hire other launch providers.

Carol Craig, the chief executive of Sidus Space, confirmed in an interview that SpaceX had a “right of first refusal” provision in a deal she had signed for five launches, allowing SpaceX to counter any offers from its competitors.

A right of first refusal, sometimes called a right to match, can foreclose competition to the extent it discourages rivals from making competitive offers to the customer. Why would a rival launch provider bother formulating a costly bid if the incumbent (SpaceX) can end the competition by simply matching the rival’s offer? Economists recognize that such provisions can generate anticompetitive effects when employed by a dominant firm and when the associated “foreclosure share” is economically significant (typically over 30 percent).

The foreclosure share, as the name suggests, is the share of the market that is foreclosed by an exclusionary contract. Consider a market in which a dominant firm supplies 80 percent of the market and half of its customers buy pursuant to a contract that contains the exclusionary provision. In that case, the foreclosure share would be 40 percent (equal to the product of 80 percent market share and 50 percent of customers with the provision). To the extent that most (or all) of SpaceX’s customers have such a provision in their contracts, the foreclosure share should easily clear the 30 percent threshold.

SpaceX could be favoring its own satellite broadband company

Predation and exclusionary contracting fit squarely within antitrust’s orbit (pun intended). Self-preferencing, on the other hand, is harder to police. A classic example is Amazon favoring its own merchandise over that of a rival merchant. SpaceX might be distorting competition in satellite broadband, a vertically related service to rocket launches. That satellite broadband rivals like OneWeb, Kacific, and Echostar rely on SpaceX for launching into space raises natural concerns about preferencing SpaceX’s affiliated satellite broadband company (Starlink). Per the Wall Street Journal story: “’It’s of course a very uncomfortable situation, where you have a supplier that wanted to go down the value chain and start competing with its own customers,’ said Christian Patouraux, chief executive at Kacific, a satellite internet company focused on Asia and the Pacific region. SpaceX launched a satellite for Kacific in 2019.”

Musk insists that SpaceX charges unaffiliated satellite broadband rivals the same as others, but query what SpaceX is charging Starlink (if anything) for launches. Ownership of Starlink also creates a conflict for SpaceX when it comes to scheduling launches for customers: “If Starship doesn’t ramp up as expected, there will likely be a shortage unless SpaceX allocates more of its Falcon fleet for customers instead of Starlink.”

Will the agencies launch a case?

SpaceX’s exclusionary contracts with customers have all the markings of an anticompetitive restraint. While predation cases are rare, SpaceX’s pricing seems oddly low relative to its incremental costs, and the chance of recoupment is high. If an antitrust agency were considering filing a Section 2 complaint against SpaceX, it should push the boundaries by challenging SpaceX’s self-preferencing as well.

Rocket launches are considered a must-have input in the process of transporting satellites, spacecraft, and astronauts in orbit. The launch industry is important to U.S. national security, and the defense agencies should aim to avoid making the government overly dependent on a monopolist, especially a predator. For the foregoing reasons, the antitrust case against SpaceX might soon have liftoff.

Wielding a sink, Elon Musk entered Twitter HQ on October 26, 2022 and proceeded to do precisely that to the platform’s reputation. Since his ascension to the Twitter throne, Musk’s actions have drawn widespread ethical and moral repudiation, motivated in part by his courting of accounts known for promoting hatred and anti-Semitism. Undaunted, Musk has pressed forward on the same path, ownership of the company bestowing upon him the latitude to act as its sovereign, unencumbered by ethical considerations and guardrails implemented in Twitter’s previous corporate structure as a public entity.

Actions have consequences, as the Merovingian once so eloquently explained in The Matrix, and Musk’s steps prompted a predictable exodus of advertisers eager to avoid any association between their brands and the sort of voices that Twitter has recently released from its digital Tartarus. Concurrently, users also began to seek out possible alternatives to the platform, as racist tweets proliferated under the new management’s permissive (if not outright sympathetic) attitude toward the far right (conducted under a “free-speech” pretext, of course). While potential Twitter alternatives had previously risen to meet consumer interest, the recent demand for Twitter substitutes represents a clear ideological reversal of the pre-Musk era. Then, the far-right wing of the Republican party, feeling slighted by the banishment of extremist voices in its ranks from Twitter, sought a suitable safe space in Parler, Gettr, and Truth Social. Notably, none of these have mustered anywhere near the audience to rival Twitter despite substantial funding and the presence of the former White House occupant on Truth Social.

Of late, potential competition to Twitter has arisen in the form of Mastodon, a six year-old open-source software platform for operating decentralized social networking services (i.e., you sign up on Mastodon on a specific server, some of which are invitation-only). Other nascent players include Nostr (an open-source protocol) and Post (a self-described source for premium news content without ads or subscriptions founded by former Waze CEO Noam Bardin). Whether these sites emerge as anything more than fringe competitors remains to be seen, though Twitter’s recent actions reveal some concern as to their likelihood of success. Which brings us to the topic of this article.

In the past several days, Twitter adopted new policies, engaging in conduct that has drawn attention in antitrust circles. Specifically, Twitter 1) suspended the official Mastodon account (@joinmastodon) then 2) implemented a new Promotion of alternative social platforms policy on December 18, 2022. The policy prohibited users from promoting themselves on other platforms while on Twitter (examples of prohibited phrases include “follow me @username on Instagram” and use of ”username@mastodon.social”). Notably, the policy allowed alternative platforms to advertise on Twitter, but prohibits users from promoting their own presence on those sites. As I explain below, this distinction informs the nature of Twitter’s anticompetitive conduct.

The fact that Twitter rolled out this policy without apparent regard for its alignment with antitrust laws outside the United States offers some insight into Musk’s haphazard and whimsical leadership. As many across social media pointed out, the new policy appears to violate the European Commission’s Digital Markets Act, which, inter alia, states that gatekeeper platforms may not “prevent consumers from linking up to businesses outside their platforms.” The DMA levies significant penalties for non-compliance: up to 100% of total worldwide annual turnover (sales) and up to 20% in the event of repeated infringements. The question of whether Twitter qualifies as a gatekeeper platform remains, though the likelihood of the answer being yes appears  rather evident: Twitter deleted the policy from its web site by approximately 10:15pm on the same day it published it (December 18, 2022).

The question of whether the policy still exists in substance if not in form aside, let’s see how it would fare in the generally more permissive US antitrust arena.

Judging by some of the articles recently posted, the immediate focus appears to lie with whether Twitter has the freedom of refusal to deal. In other words, does Twitter have any statutorily-enforceable duty to deal with its actual or potential competitors? While regulatory agencies generally permit a business to choose its partners as it deems fit, the existence of market power and its likely exercise thereof place some boundaries on such freedom. For example, in US v. Dentsply, the 3^rd Circuit explained that “Behavior that otherwise might comply with antitrust law may be impermissibly exclusionary when practiced by a monopolist.” Further, Twitter’s refusal to deal in this case rests less vis-à-vis its competitors and more with regard to its own customers. In other words, the extent to which Twitter has “refused” to deal with Mastodon, for example, is only by suspending its Twitter account. (Notably, it has NOT done the same for Facebook, Instagram, TikTok, or even Parler.) In contrast, Twitter has flexed its power over its own users, threatening them with requiring deletion of tweets and temporary account suspension for isolated incidents or first offenses to permanent suspensions for subsequent offenses.

Condemnation of such actions under antitrust law (i.e., the Sherman Antitrust Act) has legal precedent. For example, Lorain Journal Co. v. United States involved the case of a dominant newspaper (the Lorain Journal), which sought to foreclose competition from the Elyria-Lorain Broadcasting Company, which operated a radio station called WEOL located eight miles south of Lorain. A “substantial number of journal advertisers” also sought to advertise on WEOL, to the chagrin of the Lorain Journal, which conceived a plan to decline “local advertisements in the Journal from any Lorain County advertiser who advertised or who appellants believed to be about to advertise over WEOL.” The Journal monitored the radio station’s advertisers, and terminated the contracts of those that advertised there, agreeing to reinstate their ability to advertise in the Journal only after they had ceased advertising on WEOL.

The court found that the Journal’s intent was to “destroy the broadcasting company” and that “Having the plan and desire to injure the radio station, no more effective and more direct device to impede the operations and to restrain the commerce of WEOL could be found by the Journal than to cut off its bloodstream of existence — the advertising revenues which control its life or demise.”

Note the Court’s use of the term “direct”. We’ll come back to that in a moment.

Importantly, the Supreme Court did not find that the Journal’s scheme had to be successful to establish a case of attempted monopolization. Rather, the injunctive relief “sought to forestall that success” and save WEOL.

Why would such precedent apply here? After all, Twitter does not prevent users from having accounts on Mastodon, for example, they just cannot advertise doing so on Twitter. The goal, however, remains the same: to deprive Mastodon or a similar competitor of the required competitive oxygen required for critical mass. In the case of digital platforms, that oxygen comes in the form of network effects. The necessity of benefiting from such effects forms a substantial barrier to entry for nascent platforms.

Network effects occur when one customer of a particular product benefits from its use by other customers. For example, part of the attraction of a dance club lies in its popularity with other individuals. The term social “network” implies exactly such effects – users benefit from interaction with each other. Curtailing a club or a social network’s ability to increase its customer base threatens its very existence. Such network effects carry critical importance among digital platforms – they sustain industry behemoths like Facebook, Google, Amazon, YouTube and others, and they serve the same function with Twitter.

But wait, you ask, this explanation still doesn’t address the key point: can’t people just establish the same network effects at Mastodon? To address this question, let’s introduce two more related economic concepts: (1) transaction costs and (2) lock-in.

Transaction costs are just that: costs that a participant in an exchange must incur to consummate that transaction. In this case, such costs take two primary forms – the costs of moving one’s own account, and the cost of others not moving theirs, the latter reflecting a coordination problem. Take the case of a popular Twitter user with many followers. That users has expended substantial effort in establishing a follower base and will be loath to migrate to a different platform if that base does not follow or if she risks losing a substantial portion of it and must rebuild the rest. In turn, the user with few followers maybe less concerned with losing their own base and more concerned with moving to a platform that does not have key accounts of interest, requiring the user to multi-home (expend effort across multiple platforms rather than just one).

Such risks of starting anew elsewhere represent transaction costs associated with that migration. These costs also create lock-in, an economic inertia that occurs when a customer becomes dependent on the services of a single vendor, allowing that vendor to exert some degree of market power over the consumer (more on this in a second). For example, lock-in features prominently among legacy mainframe users, who cannot readily migrate certain workloads off the mainframe to the cloud, in large part because their mission critical applications rely on legacy code written in COBOL over the last fifty-plus years. Readers may remember New Jersey Gov. Phil Murphy’s April 2020 call for volunteer COBOL programmers who could help the distribution of unemployment aid during the initial phases of the COVID-19 pandemic.

The same concept applies here. Many Twitter users have established deep roots on Twitter, which has become a de facto archive of evidence. One can search for posts, articles, and the like for years prior, from institutions and users across the world. When autocracies crack down on dissidents or mass protests rise up to voice the will of the people, images often first appear on Twitter, where they are recorded for posterity and remain as a chronicle of humanity’s early experimentation with technology. While Twitter users can save and download their own archives, their whole as it appears on Twitter is surely greater than the sum of their individually-distributed parts.

Critically, the presence of lock-in indicates that the company that wields it has market power, commonly a critical ingredient when evaluating actual or potential anticompetitive conduct. What do we mean by that? In a recent CNN piece, Brian Fung defined the term as “dominance in a specific market that regulators would be expected to describe and explain in any lawsuit.” While this definition may reflect its understanding in the vernacular, Mr. Fung’s definition doesn’t accurately capture the concept.

In economic terms, market power just means the ability to set price above marginal cost. In other words, market power arises when a firm can set its own price above levels that would predominate under competitive conditions. Monopoly power, in cases of unilateral conduct (such as the present), “is the power to control prices or exclude competition.” But doing so may just reflect a firm’s superior business acumen, exploitation of which does not invite antitrust scrutiny, as the Supreme Court established in US v. Grinnell Corp. (1966). However, “Where monopoly power is acquired or maintained through anticompetitive conduct, however, antitrust law properly objects.” The relevant question at hand is whether Twitter’s recent conduct falls into this category. More importantly, however, the question we truly want to answer is whether Twitter’s actions harm competition or, as the Supreme Court explained in FTC v. Indiana Fed’n of Dentists, its actions generate “potential for genuine adverse effects on competition.”

As the late legal scholar Phillip Areeda noted (and the Court cited in Indiana Fed’n), market power is but “a surrogate for detrimental effects.” Economists and competition scholars have two primary methods of informing the existence of such detrimental effects (i.e., harm to competition) at their disposal: (1) direct evidence, and (2) indirect inference. Direct evidence is exactly that: observational evidence that a company (or a group in the case of collusive conduct) has attempted to exclude competition or raise its price above competitive levels (or lower output).

Absent such direct evidence, we may infer anticompetitive effects indirectly by defining a “relevant market” and calculating market shares. But market definition is not a requirement nor does it exist in a vacuum – its sole purpose is to illuminate market power and permit the inference of anticompetitive conduct. (It is however true that Courts have commonly required that Plaintiffs delineate at least “the rough contours” of a relevant market.)

For example, in the NCAA antitrust cases, the fact that defendant schools colluded to fix athlete wages below competitive levels was clear and obvious. Defendants admitted as such and the bylaws enshrined their conduct. These facts represented direct evidence of anticompetitive conduct. Attempting to define a relevant market adds little, if anything at this point and represents largely a Rube Goldberg machine, a complex exercise designed to prove the already obvious.

Nonetheless, let’s apply both methods here. First, do we have any evidence of monopoly power and its exercise to the detriment of competition? Absolutely. Twitter’s recent actions have illuminated the existence of lock-in through power it affords the platform over its users. You might respond, “Wait a second, Twitter offers a freemium model – using the platform is free, unless one wants blue checkmark available through the $8/month Twitter Blue subscription.”

Not quite. Digital platforms like Twitter, Facebook, or YouTube are not “free”. Just as in a barter economy, they require in-kind payment. The platforms give users access, while the users provide critical data that the platforms then sell to advertisers. As Judge Koh explained in her January 13, 2022 order in Klein et al. v. Facebook,

“In other words, users provide significant value to Facebook by giving Facebook their information—which allows Facebook to create targeted advertisements—and by spending time on Facebook—which allows Facebook to show users those targeted advertisements. If users gave Facebook less information or spent less time on Facebook, Facebook would make less money.”

The same applies to Twitter. In-kind transfers represent the operative currency on digital platforms that use such models. The platform can “raise the price” to the user by 1) diluting the quality of the user’s experience on the site or 2) taking steps to prevent the user from multi-homing or de-platforming entirely. The European Commission’s prohibition of such actions through the DMA reflects precisely these concerns.

Twitter has done exactly that, as evidence by the increase in racial animus, decline of content moderation and gutting of staff responsible for maintaining site quality. More directly, Twitter has threatened its users with banishment if they reveal their use of another platform or solicit actual or prospective followers to follow them on another platform. Doing so increases the user’s costs, particularly to the extent that a user leverages such platforms for brand-building and cannot cross-pollinate across them. A user may do so, to avoid lock-in – Twitter’s actions reflect an acknowledgement of this motivation and a desire to maintain the power that lock-in grants it over its users. Its recent ban on multiple journalists under the specious pretext of “security” represented a disciplinary tool for its broader user base, not so subtly implying that “if we can ban them, we can certainly ban you.” If users could decouple from Twitter without losing their efforts and temporal investments, such threats would be self-defeating on the part of the platform. Such threats reflect no exercise of superior business acumen but rather a desire to maintain a dominant position by undercutting possible alternatives and avoiding the crucible of competition.

Now let’s turn to the second means of establishing harm to competition: indirect inference through a relevant market definition. First, let’s clarify one point that motivates this exercise: We want to determine which competitors, if any, could discipline Twitter’s ability to raise prices to its users or otherwise harm competition.

In case of regulatory intervention, market definition would likely involve substantial amount of data analysis. Fortunately, given the digital nature of such markets, data are plentiful. Aside from Defendant data, third parties such as Comscore, Nielsen, and Semrush either collect their own data, contract with third parties to obtain it, or both (as in the case of Comscore, for example.) Of course, for the purposes of this article, I did not have access to the more expensive sources, so I relied on Semrush’s collected data.

Twitter operates as a microblogging service where users can post short messages accompanied by links or images. The service maintains a searchable repository of such messages (“tweets”), forming a historical records. Other sites provide similar services, though among the microblogging sites, Twitter dominates in terms of user share, as the table below shows, with a 99% share of total visits and 95% share of unique visitors.

Visitor Data for Major Microblogging Services, November 2022

Source: Semrush Traffic Analytics

Site	Visits	Unique Visitors	Market Share (Visits)	Market Share (Visitors)
twitter.com	8,300.00M	2,200.00M	99.32%	95.45%
truthsocial.com	30.30M	91.00M	0.36%	3.95%
gettr.com	12.30M	4.80M	0.15%	0.21%
joinmastodon.org	7.80M	5.70M	0.09%	0.25%
post.news	3.10M	2.20M	0.04%	0.10%
parler.com	1.90M	0.66M	0.02%	0.03%
tribel.com	1.30M	0.53M	0.02%	0.02%
nostr.com	0.0025M	0.0015M	0.00003%	0.00007%

Of course, a likely rejoinder would posit that a market definition should include social media giants Facebook and its subsidiary Instagram, along with perhaps TikTok and Reddit. However, if these platforms could discipline Twitter, we would not have observed the proliferation of right-wing microblogging sites Truth Social, Parler, Gettr, and Rumble (nor their spectacular failures). For the interested reader, I’ve included a larger table that may be of interest at the conclusion of this article.

Twitter’s dominant market share reflects the direct evidence of anticompetitive harm: the platform has sufficient market power to deprive nascent competitors that could threaten its hegemony and increase users’ costs of using the site (even if such costs are not measured in fiat currency).

Whether such evidence prompts regulatory agencies to take steps to curtail Twitter’s antics  remains to be seen. The harms appear to align with the type of conduct prohibited by Section 2 of the Sherman Act (unilateral attempt to monopolize) and Section 5 of the FTC Act (unfair or deceptive acts or practices). Nonetheless, as this article demonstrates, the evidence indicates that Twitter has the ability to harm competition and has already launched an attempt to do so by restricting users’ abilities to migrate to other nascent platforms. As Musk himself tweeted:

Finally, for readers interested in the various performances of microblogging and social media sites in this market periphery, I report the November 2022 data from Semrush for these platforms. The green and yellow figures below the November data reflect the performance relative to October 2022 (e.g., Twitter visits fell by 6.14% but unique visitors rose by 1.79%).

November 2022 Traffic for Social Media/Microblogging Platforms

(Source: Semrush Traffic Analytics)