In re Luckin Coffee Inc. Securities Litigation

The January 31 abnormal return is not statistically significant

My event study finds that on January 31, 2020, the date of the Muddy Waters short-seller report, Luckin's ADS experienced an abnormal return of approximately negative 7.24 percent, but the associated t-statistic of negative 1.53 does not reach the 95 percent confidence threshold (p = 0.1261), meaning the price movement on that date is not statistically distinguishable from normal market noise under my model.

It therefore cannot be established as a corrective disclosure on price impact alone

Because the January 31, 2020 abnormal return is not statistically significant, the Muddy Waters report cannot be established as a legally cognizable corrective disclosure on the basis of price impact alone, and the defense position is reinforced by the fact that Luckin denied the allegations the same day and a prominent investor publicly rebutted the report.

The April 2 abnormal return is significant at any conventional threshold

My event study finds that on April 2, 2020, the date of Luckin's own board disclosure of fabricated transactions, the abnormal return was approximately negative 78.54 percent, with a t-statistic of negative 15.72 (p essentially zero), which is statistically significant at any conventional threshold.

But the April 2 decline is confounded and must be disaggregated

Although the April 2, 2020 abnormal return is statistically significant, the magnitude of that single-day decline, over 75 percent, reflects a confluence of value-relevant information beyond the fraud admission itself, including the simultaneous halt of trading, the prospect of NASDAQ delisting, and broader market conditions during a period of acute volatility, all of which must be disaggregated before the fraud-specific component of the price decline can be attributed to the alleged misrepresentations.

The event study is the right tool, applied under a principled protocol

An event study is the appropriate tool for assessing the loss causation aspect of a securities fraud claim, and the methodology I applied is consistent with that standard, but the selection and classification of event dates must follow a principled protocol grounded in the plaintiff's own allegations rather than post-hoc selection.

The low R-squared limits what a single-index model can attribute

The low R-squared values in my market model (0.123 for January 31 and 0.18 for April 2) indicate that the SPY benchmark explains only a modest fraction of Luckin's daily return variation, which is consistent with a thinly followed foreign private issuer whose price movements are driven substantially by firm-specific and China-market factors not captured by a US equity index, raising questions about the adequacy of any single-index model for this security.

Reasoning arc

I begin from the event study I conducted, which is the standard econometric tool for assessing price impact and loss causation in securities fraud matters. For the January 31, 2020 date, the data show a price decline that is directionally consistent with the plaintiff's theory but falls short of statistical significance at the 95 percent level; I cannot conclude that the Muddy Waters report caused a fraud-related abnormal return distinguishable from noise. For the April 2, 2020 date, the abnormal return is unambiguously significant, but statistical significance is a necessary condition for loss causation, not a sufficient one: the question is whether the entire decline, or only a portion of it, is attributable to the revelation of the alleged fraud as opposed to the trading halt, delisting risk, and contemporaneous market disruption. My opinion is that the evidence does not establish a clean, unconfounded corrective disclosure on January 31, and that the April 2 decline requires disaggregation before any damages figure derived from it can be accepted as reliable. I express no opinion on scienter, materiality as a legal standard, or ultimate liability; those determinations belong to the Court and the trier of fact.

Caveats and limits, stated by the witness

The archetype states its own vulnerabilities before opposing counsel does, which is what makes the cross-examination artifact that follows worth reading:

• My market model uses SPY as the sole benchmark index. Luckin is a China-based issuer whose ADS price may be more closely correlated with Chinese equity indices or consumer-sector benchmarks; omitting a China-market or sector control is a model specification choice that opposing counsel may contest, and I acknowledge it affects the precision of the abnormal return estimates.
• The low R-squared values in my estimation regressions (0.12 to 0.18) mean that a substantial portion of Luckin's daily return variation is unexplained by the market model, which increases the standard error of the abnormal return estimates and reduces the power of the statistical tests, particularly for the January 31 event.
• I have not performed a full Cammer factor analysis on the record available to me; to the extent Luckin ADSs did not trade in an informationally efficient market during the class period, the foundational assumption of the event study and the Basic presumption of reliance would require further examination.
• The April 2, 2020 price decline occurred simultaneously with a trading halt and subsequent delisting proceedings; I have not yet quantified the independent price impact of those structural market events, and any damages model that attributes the full 78 percent abnormal return to the fraud disclosure alone without accounting for those factors would overstate recoverable loss.
• My opinion addresses statistical price impact and does not constitute a complete damages model; a workable, class-wide damages methodology consistent with the theory of liability would require additional analysis that I have not yet performed.

January 31 non-significance does not negate price impact given the model's low R-squared

Event-study reliability under Daubert requires a well-specified model; a model with an R-squared of 0.123 explains only 12.3 percent of return variation, undermining the non-significance finding.

The defense expert's own market model produced an R-squared of only 0.123 on the January 31 event date, meaning the regression explains barely one eighth of the stock's daily return variation. A t-statistic of negative 1.53 and a p-value of 0.1261 are close to the 5 percent threshold, and the low model fit inflates standard errors, making non-significance a product of model weakness rather than genuine absence of price impact. The expert cannot credibly claim the 7.24 percent abnormal decline on January 31 was noise when the model itself is poorly specified.

Lineage · Market grounding: January 31 event, t-stat -1.53, p-value 0.1261, R-squared 0.123. Archetype W4 (failure to control for confounding) and W6 (model specification).

Inability to identify any non-fraud confounding event on April 2 to dilute the 78.5 percent abnormal decline

Loss causation requires isolating fraud-specific price impact; a defense expert who cannot name a specific contemporaneous non-fraud event cannot argue the April 2 decline was confounded.

The April 2, 2020 abnormal return of negative 78.543 percent is statistically significant at any conventional threshold (t-stat -15.723, p-value effectively zero). The only filing near that date is a routine 6-K with no decoded material items. The defense expert must either identify a specific non-fraud channel that caused a 75-plus percent single-day collapse or concede the entire decline is attributable to the company's own admission of fabricated sales. Courts have rejected event studies that attribute price movements to confounding events without specifying the channel.

Lineage · Market grounding: April 2 event, t-stat -15.723, p-value 0.000, abnormal return -78.543 percent. EDGAR confounding candidates show only a routine 6-K with max relevance none. Archetype W3 and W4.

Treating January 31 as non-corrective while the company's own April 2 admission confirms the same fabrication

A corrective disclosure need not be the company's own admission; a third-party report that reveals the same fraud later confirmed by the issuer can qualify, and the classification is internally inconsistent.

The defense expert's position that the January 31 Muddy Waters report was not a legally cognizable corrective disclosure is undercut by the April 2 company admission, which confirmed the identical fabrication Muddy Waters alleged. If the expert classifies January 31 as non-corrective, the expert must explain why a report citing 11,260 hours of video and 25,843 receipts alleging the same RMB 2.2 billion fabrication later confirmed by the board does not partially reveal the fraud. Courts have scrutinised defense experts who classify disclosure dates inconsistently with the underlying allegations.

Lineage · Scenario: January 31 contested corrective disclosure; April 2 definitive corrective disclosure confirming the same fabrication. Archetype W6 (event-date classification) and W3 (loss causation).

Failure to quantify the incremental fraud-related component of the April 2 decline

An expert who asserts a confounding effect but offers no quantitative method for isolating it fails the reliability requirement under Rule 702.

If the defense expert argues that some portion of the April 2 decline reflects non-fraud factors such as COVID-19 market conditions or pre-existing business deterioration, the expert must provide a quantitative method for apportioning that portion. Asserting that some part of the decline is non-fraud without a model for measuring it is the same methodological failure courts have identified when an expert simply asserts a number without showing the work.

Lineage · Market grounding: April 2 residual -78.543 percent after SPY control. Archetype W3 (loss causation) and W7 (absent methodology for apportionment).

High beta on the January 31 window versus low beta on the April 2 window signals an unstable benchmark

Inconsistent model parameters across event windows indicate the benchmark is not stable, undermining the reliability of abnormal return estimates for both dates.

The defense expert's own market model estimated a beta of 2.2 for the January 31 event window and a beta of 1.047 for the April 2 event window, a more than twofold difference across estimation windows covering the same class period. This instability in the core regression parameter means the benchmark used to compute abnormal returns is not consistent, and the expert must explain why the model is reliable when its central parameter shifts so dramatically between the two key event dates.

Lineage · Market grounding: beta 2.2 (January 31 window) versus beta 1.047 (April 2 window). Archetype W6 (event-window and model specification) and W4 (failure to test alternative specifications).

1. January 31, 2020 short-seller report as a legally cognizable corrective disclosure

Fit · FRE 702 fit; loss causation under Rule 10b-5

The January 31, 2020 Muddy Waters report is an anonymous short-seller publication, not a company or regulatory disclosure. Luckin denied all allegations the same day, and Citron Research publicly rebutted the report and disclosed a long position. The abnormal return on that date is negative 7.24 percent, with a t-statistic of negative 1.53 and a p-value of 0.1261, which is not statistically significant at any conventional threshold. Because the price movement is not statistically distinguishable from noise and the source of the alleged disclosure is a contested third-party short-seller, the event-study opinion does not fit the legal requirement that a corrective disclosure reveal the truth of the alleged fraud to the market.

2. Market model specification: low R-squared and high beta on the January 31 event date

Reliability · FRE 702 reliability; Daubert methodology testing

The market model used to generate the January 31 abnormal return carries an R-squared of only 0.123, meaning the model explains roughly 12 percent of the variation in Luckin's daily returns during the estimation window. A model with such low explanatory power produces unreliable abnormal return estimates because the residual is dominated by firm-specific noise unrelated to the alleged fraud. The beta of 2.2 on that date further suggests the estimation window captured a period of unusual volatility, raising questions about whether the control period was free of contamination from the fraud itself.

3. Failure to isolate fraud-specific price impact from confounding events on April 2, 2020

Reliability · FRE 702 reliability; loss causation fit

The April 2, 2020 price collapse of over 75 percent occurred simultaneously with the company's own disclosure of fabricated sales, the halt of ADS trading, and the onset of NASDAQ delisting proceedings, each of which independently carries value-relevant information for investors. An event study that attributes the entire negative 78.54 percent abnormal return to the fraud-related disclosure, without separately quantifying the contribution of the trading halt, delisting risk, and broader market conditions during a period of significant COVID-19 volatility, fails to isolate the fraud-specific component of the price decline.

4. Absence of a workable class-wide damages quantification model

Reliability · FRE 702 reliability; Comcast fit requirement

The plaintiff's event study identifies price declines on two alleged corrective-disclosure dates but does not present a disclosed, replicable methodology for translating those abnormal returns into a class-wide damages figure that accounts for the varying inflation levels across the class period, the contested status of the January 31 disclosure, and the need to exclude investors who purchased after the fraud was partially revealed. Without a damages model that is consistent with the liability theory, the event-study opinion is incomplete and cannot assist the trier of fact in calculating loss.

5. Failure to net the April 2 impact against pre-existing market awareness

Reliability · FRE 702 reliability; loss causation under Dura

By January 31, 2020, the Muddy Waters report had placed fraud allegations into the public domain, and Luckin's ADS price had already partially adjusted. Any event study that measures the April 2 price decline without accounting for the inflation already removed by the January 31 partial disclosure risks double-counting or misattributing the fraud-related component of the total class-period loss. The expert must provide a method for quantifying the incremental effect of the April 2 disclosure net of any prior partial revelation, and an opinion that simply reports the raw abnormal return on April 2 without that adjustment is not reliable.

Definitive corrective disclosure with company admission

The April 2, 2020 disclosure is the company's own board-level admission of fabricated transactions, producing a statistically significant abnormal return of negative 78.54 percent (t = -15.72, p = 0.000). A defense expert cannot credibly argue no price impact on this date, and the admission forecloses the argument that the disclosure was not legally corrective. This is the single largest upward driver of settlement value.

• Whether defendants can demonstrate that a portion of the April 2 decline reflected non-fraud information released contemporaneously.
• Whether the damages model can reliably translate the percentage decline into aggregate investor loss given the delisting and trading halt.

Contested status of the January 31, 2020 Muddy Waters disclosure

The abnormal return on January 31, 2020 is negative 7.24 percent but is not statistically significant at the 95 percent confidence level (t = -1.53, p = 0.1261). Defense experts routinely argue that an anonymous short-seller report does not constitute a legally cognizable corrective disclosure, and the non-significant result supports that position. If this date is excluded from the damages model, the class period inflation attributable to the period between January 31 and April 1, 2020 may be contested.

• Whether the court treats the Muddy Waters report as a partial corrective disclosure notwithstanding the non-significant abnormal return.
• Whether the J Capital Research follow-up on February 12, 2020 is treated as a separate corrective event.

Foreign defendant recovery risk and delisting

Luckin Coffee is a China-based issuer whose ADSs were delisted from NASDAQ following the fraud admission. Practical collection from the corporate defendant and individual defendants located in China is materially more difficult than in a domestic issuer case, and D&O insurance coverage may be limited or disputed. This structural factor depresses the achievable settlement relative to a comparably sized domestic fraud.

• Availability and limits of D&O insurance coverage.
• Whether any defendant has US-accessible assets.
• Whether the SEC enforcement action or parallel proceedings create additional recovery channels.

Absence of a quantified aggregate investor loss

No aggregate investor loss figure has been provided for this matter. Published benchmarks show that settlement values scale with estimated investor losses, and without a credible damages model the parties lack a common anchor for negotiation. Defense experts can exploit the absence of a fully articulated damages methodology to argue that plaintiffs cannot establish class-wide damages on a common basis.

• Whether plaintiffs' expert produces a damages model prior to class certification.
• Whether the model survives a Daubert challenge.

Severity and scale of the admitted fabrication

The admitted fabrication of approximately USD 310 million in sales, spanning multiple quarters and involving the COO and other employees, is among the more egregious fraud admissions in recent securities class action history. The scale and deliberateness of the misconduct increase litigation risk for defendants and support a settlement above the published median, even accounting for recovery challenges.

• Whether individual defendants cooperate or contest liability separately.
• Whether the internal investigation findings are fully disclosed and usable in litigation.

Net directional signal: expands plaintiff recovery

Confidence low. Key drivers: an unambiguous, statistically significant price collapse on April 2, 2020 tied to the company's own fraud admission; the scale of the admitted fabrication; the contested status of the January 31, 2020 Muddy Waters disclosure as a partial offset; foreign defendant recovery risk and NASDAQ delisting as structural discounts; and the absence of a quantified aggregate investor loss figure limiting the negotiation anchor.

Strategy notes

The defense's strongest lever is the non-significant abnormal return on January 31, 2020 (t = -1.53, p = 0.1261), which supports the argument that the Muddy Waters report was not a legally cognizable corrective disclosure and that the market did not treat it as revealing the fraud. This argument, if accepted, narrows the class period inflation and reduces the damages base. The April 2, 2020 disclosure is not contestable on price impact grounds given the t-statistic of -15.72, so defense strategy should focus on confounding events on that date, the appropriate damages methodology, and the practical limits of recovery from foreign defendants. Plaintiffs' strongest position is the company's own board admission, which eliminates the need to prove the underlying fraud through circumstantial evidence and makes scienter essentially conceded at the corporate level. The absence of a grounded aggregate investor loss figure is a gap that both sides should expect to fill quickly: the settlement range will compress significantly once a credible damages model is on the table. The delisting and foreign defendant structure create a genuine ceiling on achievable recovery regardless of the merits, and both sides should account for that in any mediation posture.

Scored against what actually happened

This is the site's note rather than the run's. Luckin settled the US securities class action for $175 million, inside the predicted band and above the point estimate. The run is scored against that outcome in public, including where it was wrong: the point estimate was low.