The Federal Trade Commission (FTC) sued Meta in the U.S. District Court for the District of Columbia, alleging that Meta unlawfully maintained a personal social networking monopoly by buying Instagram and WhatsApp. After the court entered judgment for Meta in November 2025, the FTC appealed to the D.C. Circuit and filed its reply brief on September 29, 2026. Argument is expected in late 2026 or in 2027.
Latest development Sep 29, 2026
On September 29, 2026, the Federal Trade Commission (FTC) filed its reply brief in the D.C. Circuit. It argues that the district court’s ruling for Meta was legally flawed on market definition and on the timing of the monopoly-power analysis. The FTC contends that Meta holds monopoly power in a personal social networking market distinct from short-form video services such as TikTok and YouTube.
Why it matters
The appeal asks whether the Federal Trade Commission (FTC) must prove current monopoly power to unwind long-completed acquisitions, or only power at the time of filing. The answer affects Meta’s ownership of Instagram and WhatsApp and future challenges to consummated deals.
Background
On December 9, 2020, the Federal Trade Commission (FTC) sued Meta Platforms, Inc. in the U.S. District Court for the District of Columbia. The FTC sought divestiture of Instagram, acquired in 2012, and WhatsApp, acquired in 2014. It alleges that Meta pursued a “buy-or-bury” strategy to protect a monopoly in personal social networking services. The FTC brought its claims under Section 13(b) of the Federal Trade Commission Act and Section 2 of the Sherman Act.
In June 2021, the court dismissed the complaint as insufficient but granted leave to replead. The FTC filed an amended complaint in August 2021, and the court sustained it in January 2022. A parallel case brought by state attorneys general was dismissed as untimely. In November 2024, the court largely denied summary judgment. A seven-week trial began on April 14, 2025, with Mark Zuckerberg as the opening witness.
On November 18, 2025, Chief Judge James E. Boasberg entered judgment for Meta. He held that TikTok and YouTube belong in the relevant market because their features have converged with those of Instagram and Facebook. That left Meta with a market share below 50% and declining. He also held that Section 13(b) is forward-looking and requires the FTC to prove current or imminent monopoly power, whatever the historical record showed. The FTC filed a notice of appeal to the U.S. Court of Appeals for the District of Columbia Circuit on January 20, 2026.
In its opening brief of May 22, 2026, the FTC argues that monopoly power should be measured when the case was filed and that TikTok’s later growth is irrelevant. On June 1, 2026, the District of Columbia and more than two dozen states filed an amicus brief supporting the FTC. Meta filed its appellee brief on August 20, 2026, and the U.S. Chamber of Commerce and other amici filed a brief supporting Meta on August 27, 2026. On September 29, 2026, the FTC filed its reply brief, contending that Meta holds monopoly power in a personal social networking market distinct from TikTok and YouTube. Argument is expected in late 2026 or in 2027.
Timeline 12 events
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FilingFTC files reply brief in D.C. Circuit appeal
The FTC argued that the district court’s ruling for Meta was legally flawed on market definition and the timing of the monopoly-power analysis. It said Meta holds monopoly power in a personal social networking market distinct from short-form video services such as TikTok and YouTube.
US FTC files reply in support restarting monopoly case against MetaFTC Presses To Revive Antitrust Case Against Meta
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FilingChamber of Commerce files amicus brief backing Meta on appeal
The U.S. Chamber of Commerce and other amici filed a brief opposing revival of the FTC’s monopolization case. They argued that the FTC’s appellate arguments seek to rewrite established antitrust law.
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FilingMeta files appellee brief in D.C. Circuit
Meta argued that the district court correctly found that, whatever Meta’s past conduct, it currently faces robust competition from TikTok and YouTube and lacks monopoly power today.
Meta Tells DC Circ. To Reject FTC AppealMeta Fights FTC Bid To Revive Monopoly Charges
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FilingStates file amicus brief backing FTC’s appeal
The District of Columbia and more than two dozen U.S. states filed an amicus brief in the D.C. Circuit supporting the FTC’s appeal of the judgment for Meta.
States Back FTC's DC Circ. Appeal In Meta Monopoly CaseUS states file amicus brief in support of FTC in Meta monopoly suitStates back FTC appeal against Meta lossMeta Antitrust Appeal: 29 States Back FTC as WhatsApp Privacy Lawsuit Intensifies Instagram Breakup Stakes
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AppealFTC files opening brief in D.C. Circuit
The FTC argued that monopoly power is measured when the case was filed. AAI filed a supporting amicus brief on May 29, 2026.
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AppealFTC files notice of appeal to the D.C. Circuit
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JudgmentCourt enters judgment for Meta, finding no current monopoly power
Chief Judge Boasberg placed TikTok and YouTube in the relevant market and held that Section 13(b) requires proof of a current or imminent violation.
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HearingTrial begins with Zuckerberg as opening witness
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OrderCourt largely denies summary judgment and sets case for trial
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OrderFTC files amended “buy-or-bury” complaint
The court sustained the amended complaint in January 2022, setting up years of discovery.
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OrderCourt dismisses FTC complaint as insufficient
The court found that the FTC had failed to plausibly allege monopoly power but granted leave to replead.
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FilingFTC sues to unwind Instagram and WhatsApp acquisitions
Experimental AI forecast
How it is madeHow will the D.C. Circuit resolve the FTC’s appeal of the judgment for Meta by December 31, 2027?
- D.C. Circuit affirms judgment for Meta62%
- Still pending on December 31, 202723%
- D.C. Circuit revives FTC’s case11%
- FTC drops appeal or settles4%
- Resolves by
- Dec 31, 2027in 14 months
- Record confidence
- Medium
The D.C. Circuit is most likely to affirm the judgment for Meta by December 31, 2027 (62%). The trial court’s market definition rests on fact findings after a seven-week trial, and those findings get deferential clear-error review on appeal.
How it resolves. Resolves on the D.C. Circuit’s decision in No. 26-5028 as shown on the public docket or in its published opinion. “Affirms” means the judgment for Meta stands in full. “Revives” means the court reverses or vacates the judgment in whole or in part and remands, or directs any further proceedings on liability or relief. “Drops appeal or settles” means the FTC voluntarily dismisses the appeal or the parties file a settlement or consent decree before a decision. “Still pending” means none of these has occurred by December 31, 2027. Later rehearing or certiorari petitions do not change the resolution.
Reasoning
Starting point. Federal courts of appeals reviewing civil bench-trial judgments for defendants, including government antitrust appeals: Federal appellate courts reverse roughly 10% to 15% of civil judgments. Bench-trial fact findings such as market definition get clear-error review, which lowers reversal odds further.
Federal courts of appeals reverse about 10% to 15% of civil judgments, and bench-trial fact findings are rarely disturbed. The FTC’s best route is legal: its argument that monopoly power should be measured at filing, not today, gets de novo review. That theory runs against the forward-looking text of Section 13(b) as the trial court read it, which limits its odds. The FTC’s market argument largely challenges factual findings on TikTok and YouTube, a harder path. Strong state amicus support signals interest but rarely changes outcomes. Briefing closed September 29, 2026, so argument likely comes in early 2027 and a decision usually follows within months, though slippage leaves real pending risk. Settlement or withdrawal is unlikely because Meta has little reason to concede structural relief after winning at trial, though a policy shift at the agency is possible. The leading alternative is a decision still pending at year-end 2027. Nothing in the record has changed since the previous forecast, so the numbers are unchanged.
Clear-error review of market definition findings after trial · De novo review of FTC’s time-of-filing monopoly theory · Briefing complete September 29, 2026, argument not yet scheduled · Meta has little incentive to settle after trial win · Possible change in FTC enforcement priorities
Generated automatically by Claude Opus 5.5 on Oct 8, 2026 from this case’s record on this site, and published without editorial review. The probabilities are the model’s judgment, not measured frequencies, and they are scored publicly as cases resolve. Not legal or investment advice. How the forecasts are made
Disclosure: Anthropic, which makes the model that wrote this forecast, competes with or has commercial ties to a party to this case.
What it would mean
If the D.C. Circuit affirms, Meta keeps Instagram and WhatsApp and no money changes hands. The FTC seeks divestiture, not damages. An affirmance would remove the structural threat to Instagram, which eMarketer estimated would bring in more than $32B in U.S. ad revenue in 2025. When Meta won at trial on November 18, 2025, its shares closed down 0.3% at $600. An affirmance would also make current or imminent monopoly power the test in the D.C. Circuit for FTC suits to unwind completed deals.
If the D.C. Circuit revives the case, divestiture of Instagram and WhatsApp returns as a possible remedy. A breakup would still be years away. The case would go back to the district court for further findings and a remedy phase, and further appeals could follow. Meta’s market value of about $1.9T and cash of about $90B rule out any question of ability to pay. The real stake is separating a business with more than $32B in U.S. ad revenue. A ruling that measures power at filing would also strengthen FTC challenges to other completed acquisitions.
Money, who pays, markets and what to watch
Two steps ahead. If the case is revived, the FTC’s win would be about the legal test, not a breakup. Liability would rest on a market as it stood at filing. Any remedy would have to fit the market as it stands years later, after TikTok’s rise. That gap gives Meta strong arguments against full divestiture even after losing the appeal. It could also make negotiated terms, such as advance notice of future acquisitions, a realistic end point for the 4% settlement path.
The money
- Meta Platforms: $32B a year of revenue at stake. Annual revenue a divestiture remedy would put at stake. eMarketer estimated Instagram would top $32B in U.S. advertising revenue in 2025, about half of Meta’s U.S. ad sales. This is a floor. It excludes Instagram’s non-U.S. revenue and WhatsApp, for which no reliable standalone revenue figure is published. Divestiture is the only remedy sought. No damages or fines are at issue. Only if the D.C. Circuit revives the case. Revenue would be at stake after a remand, a liability and remedy phase in the district court, and any further appeals. Nothing moves under an affirmance or while the appeal is pending.[1] That is 16% of its annual revenue ($201B, Dec 31, 2025).
- Figures used: Meta Platforms, market value $1.9T (Oct 5, 2026)[2] · Meta Platforms, cash $90.3B (Jun 30, 2026)[3] · Meta Platforms, annual revenue $201B (Dec 31, 2025)[4]
Who pays
- Meta Platforms alone bears the consequences. The FTC seeks divestiture of Instagram and WhatsApp, not damages, so no insurer, indemnitor, co-defendant, or litigation funder shares the exposure.
- A parallel suit by state attorneys general was dismissed as untimely. The states now appear only as amici, so no follow-on state damages claim rides on this appeal.
- On the FTC side, taxpayers fund the appeal. Any revived case would mean more years of agency trial and remedy litigation against a company that reported $200.97B in 2025 revenue.[4]
- Meta’s balance sheet can absorb the litigation itself. It held $90.26B in cash and marketable securities and $83.66B in long-term debt as of June 30, 2026.[3]
Markets
- Meta Platforms Class A shares (Nasdaq: META) closed down 0.3% at $600 on November 18, 2025, the day the district court entered judgment for Meta.[5]
- Meta’s market value was about $1.89T as of October 5, 2026. Its listed shares and its bonds are the main securities tied to this appeal.[2][3]
- Meta’s long-term debt rose from $58.74B at December 31, 2025, to $83.66B at June 30, 2026. A revived divestiture case would raise questions about how debt and assets would be split.[4][3]
- Instagram was expected to generate about half of Meta’s U.S. ad sales in 2025, per eMarketer. That share is why any revival would matter most for how investors value a breakup.[1]
Collecting
- No money judgment is at stake, so there is nothing to collect. A remedy would come as a district court divestiture order against a U.S. company with U.S. assets, enforced by that court.
- If the panel revives the case, Meta could seek rehearing en banc and Supreme Court review before any remand proceeds. That would push any structural order further out.
- Even after a revival, the FTC would still have to win on liability and remedy in the district court. A divestiture would then likely face its own appeal before any separation took effect.[6]
Beyond the parties
- An affirmance would bind district courts in the D.C. Circuit, the FTC’s home forum, to require proof of current or imminent monopoly power under Section 13(b). That would make it harder to unwind deals closed long ago.[6]
- A ruling that power is measured at filing would strengthen challenges to completed acquisitions across the technology sector. The District of Columbia and more than two dozen states backed that position as amici.[7]
- The U.S. Chamber of Commerce argued that the FTC is trying to rewrite established antitrust law. Its brief shows that business groups see the timing rule as reaching well beyond Meta.
- The market-definition issue, whether TikTok and YouTube compete with Instagram and Facebook, would guide how courts and agencies define digital markets in future monopolization cases.[8]
What to watch
- Late 2026 or 2027D.C. Circuit hears oral argument on the FTC’s appeal of the judgment for Meta
- After argumentD.C. Circuit rules on market definition and the timing of the monopoly-power test
- After a panel decisionLosing side decides whether to seek rehearing en banc or Supreme Court review
- Early 2027Meta’s 2026 annual report updates its disclosure of the FTC litigation[4]
Sources
- Instagram Expected to Generate 50% of Meta’s U.S. Ad Sales in 2025 finance.yahoo.com · 2024-12-18
- Meta Platforms (META) Market Cap & Net Worth stockanalysis.com · 2026-10-05
- Meta Reports Second Quarter 2026 Results (Form 8-K Exhibit 99.1) sec.gov · 2026-07
- Meta Platforms, Inc. Annual Report FY2025 (Form 10-K) sec.gov · 2026
- Meta Wins FTC Antitrust Trial Over Instagram, WhatsApp Deals news.bloomberglaw.com · 2025-11-18
- Meta Prevails in FTC’s Antitrust Case Challenging Instagram and WhatsApp Acquisitions sullcrom.com · 2025-12
- AAI Urges D.C. Circuit to Vacate District Court’s Market Definition and Monopoly Power Errors in FTC Challenge to Meta’s Instagram, WhatsApp Acquisitions antitrustinstitute.org · 2026-06-01
- FTC Presses To Revive Antitrust Case Against Meta mediapost.com · 2026-10-06
Experimental AI analysis by Claude Opus 5.5 on Oct 8, 2026, built on the forecast above from this case’s record and public sources found by the model’s own web search. Figures are estimates as of the dates shown, and shares of value are computed by the site from the figures cited. Published without editorial review. Nothing here predicts the price of any security or is investment advice. How it is made
Disclosure: Anthropic, which makes the model that wrote this analysis, competes with or has commercial ties to a party to this case.