Expert Witness Profiler

Tag: Seller

  • Compliance Expert Was Allowed to Opine on Amazon Policy

    Compliance Expert Was Allowed to Opine on Amazon Policy

    ZAGG initiated this action against DVG, TX Trading Inc. (“TX Trading”), and Menachem Mendel Ichilevici (“Ichilevici”) (collectively, “Defendants”), alter egos collectively doing business as Amazon Seller “Mac N’ Cheese,” violated Sections 32 and 43 of the Lanham Act, 15 U.S.C. §§ 1114, 1125(a), by infringing on ZAGG’s trademarks and falsely advertising ZAGG products.

    Plaintiff, ZAGG, Inc., filed a Daubert motion to exclude the report and testimony of DVG’s Amazon policy expert, Rachel Johnson Greer.

    Compliance Expert Witness

    Rachel Johnson Greer worked as a Program Manager at Amazon for five years, overseeing various elements of Amazon’s compliance programs. She has has served as an Amazon compliance consultant since 2015. Greer published a book on Amazon product safety. She has appeared as an “Amazon Product Compliance” speaker at various events from 2016 to 2022.

    Greer received a Master of Business Administration degree from Seattle University.

    Discover more cases with Rachel Johnson Greer as an expert witness by ordering his comprehensive Expert Witness Profile report.

    Discussion by the Court

    I. Qualifications

    ZAGG claimed that Greer is “an unqualified and unreliable witness as to Amazon’s current processes and policies (or any policies after she left in 2017).”

    However, Greer’s experience both as a manager at Amazon and as a consultant to Amazon sellers qualifies her as an expert in the field of “Amazon policy compliance.”

    Despite Greer’s demonstrated experience in the Amazon marketplace, ZAGG attacked her qualifications in four ways. First, ZAGG claimed that none of Greer’s roles at Amazon “involved any of the issues or policies at issue in this case.” But that’s not entirely true. Greer “investigated sellers and vendors for safety and intellectual property infringement,” “managed quality & compliance for Amazon’s own brands,” and “managed the legal compliance of all global imports.”

    Second, ZAGG contended that Greer isn’t qualified because she hasn’t worked at Amazon since 2017 and thus (ZAGG says) isn’t familiar with Amazon’s “current processes and policies.” But ZAGG hasn’t cited any authority for the proposition that an expert must be currently (or even recently) employed by a company whose policies he or she intends to outline.

    Third, ZAGG insisted that “only Amazon itself can testify as to its practices and procedures.” However, courts routinely allow experts who are unaffiliated with a company to testify about that company’s policies or practices if those experts are otherwise qualified to do so. To the extent ZAGG thinks that Amazon would be a better witness, it hasn’t identified any authority that requires the Court to exclude an expert’s testimony simply because a better witness might have been found.

    Finally, ZAGG claimed that Greer is impermissibly trying to “testify on behalf of Amazon.” The Greer Report made it clear that Greer is offering her perspective on Amazon’s policies and practices as an expert who’s navigated the Amazon marketplace for years.

    II. Reliability

    Because Greer is a non-scientific expert testifying about her experience, the relevant question is “how that experience leads to the conclusion reached, why that experience is a sufficient basis for the opinion, and how that experience is reliably applied to the facts.”

    Greer has shown that her opinions about Amazon’s policies and practices are based, in part, on her experience “providing compliance guidance to Amazon sellers regarding Product Policy, Fulfilment by Amazon (‘FBA’) compliance, Amazon’s intellectual property policies, and other Seller Performance issues,” and “providing advisory services on meeting Amazon and regulatory product compliance requirements for consumer goods.”

    Her “opinions in this case are based on her experience working at Amazon and in her Amazon consulting business, Amazon policy documents, publicly available listings of ZAGG products on Amazon.com, and her review of certain documents provided to her by DVG.” That’s more than sufficient for the Court to find her report and testimony reliable under Rule 702.

    Since Greer’s proposed testimony is based on her personal experience working with Amazon’s quality control policies over many years, the Court denied the second aspect of ZAGG’s motion.

    III. Helpfulness

    ZAGG argued that the Greer Report is not helpful because it “contains exclusively fact testimony and is completely devoid of any opinions that go beyond the understanding of an average layperson.”

    However, DVG argued that Greer does much more than just recite Amazon policies and procedures. In saying so, DVG identifies several of Greer’s opinions that (it believes) will help the trier of fact, including:

    • Amazon public-facing policies “are often contradictory or outdated” because “Amazon’s process for changing and updating policies, guidelines and other seller documents on the Amazon Marketplace is a multi-step process that requires internal tickets and up to six approvals.”
    • “Based on her experience at Amazon and in providing consulting services to Amazon sellers, it has always been understood that a “new” item is simply one that is brand-new and unused, free of blemishes, smudges or dirt, and in the original packaging.”

    The Court agreed with DVG that Greer’s report and testimony go well beyond a mere recitation of Amazon’s policies and that her expert analysis of Amazon’s policies and practices would assist the trier of fact. The Court thus denied this third aspect of ZAGG’s motion.

    IV. Opinions & Hearsay

    First, ZAGG said that “it is entirely unclear what ‘opinions’ are being offered by Greer.” ZAGG claimed that the Greer Report is “a hodgepodge of speculative factual assertions made by Greer masquerading as ‘opinions.’”

    However, in making this argument, ZAGG identified several of Greer’s specific opinions—thus belying its claim that it has no way of knowing which opinions Greer plans to offer. (“Greer testified that she is offering only two opinions. First, she testified that: ‘Accordingly, it is my opinion that ZAGG’s conclusion that defendants cannot list ZAGG products as being in new condition is based on an incorrect interpretation of Amazon’s policies that is not used by Amazon in practice.’ Second, she testified that: ‘it is my opinion that defendants’ stickering of ZAGG products comports with Amazon’s policy, as does the marking over the barcode on the lower left of the packaging above.’”)

    Second, ZAGG believed that Greer’s opinions are merely “out-of-court assertions about Amazon’s policies and practices, offered for their truth.”

    The Court held that Greer’s testimony isn’t a mere recounting of the out-of-court statements of others—it’s expert analysis about the industry’s business practices gleaned from her years of experience as an Amazon employee and consultant.

    Held

    The Court denied ZAGG’s motion to exclude the report of DVG’s expert, Rachel Johnson Greer.

    Key Takeaway

    Knowledge of an industry’s business practices is gleaned from years of working within the industry and with its professionals. It is not a recounting of out of court statements of others.

    Case Details:

    Case Caption: Zagg Inc. V. TX Trading, Inc.
    Docket Number: 1:23cv20304
    Court Name: United States District Court, Florida Southern
    Order Date: December 16, 2025
  • Economics Expert’s Testimony on Anti-Discounting Policies Admitted

    Economics Expert’s Testimony on Anti-Discounting Policies Admitted

    Plaintiffs sued Amazon.com, Inc., claiming that the company violated the Sherman Act. They contended that Amazon denied customers the “benefits of lower prices and fees” that would arise in a competitive market; and they said Amazon did so by imposing on third-party sellers “Most Favored Nation” policies that cause customers to pay supra-competitive prices. 

    Plaintiffs’ economics expert Dr. Parag A. Pathak, Ph.D. concluded that Amazon’s anti-discounting policies and practices collectively function as a Platform Most Favored Nation (PMFN) restraint.

    According to Pathak, Amazon is the largest online marketplace in the United States, with a market share of around 72% in the Online Retail Marketplaces Market. He added that Amazon’s conduct prevents price competition with other online retailers, which in turn allows Amazon to charge “monopoly referral fees—i.e., the price of connecting merchants and consumers to each other and completing the sales transaction between them.”

    Amazon filed a motion to exclude Pathak’s expert testimony.

    Economics Expert Witness

    Dr. Parag A. Pathak, Ph.D. is the Class of 1922 Professor of Economics at Massachusetts Institute of Technology. He is also a Research Associate at the National Bureau of Economic Research (NBER) and is the founding Director of the NBER’s working group on market design. 

    Want to know more about the challenges Parag Pathak has faced? Get the full details with our Challenge Study report. 

    Discussion by the Court

    Pathak explained that microeconomic modeling shows that, “all else equal, a marketplace with market power (like Amazon) sets higher fees when merchants are constrained by an anti-discounting policy than when they are not.” He said that in this situation, “because merchants cannot discount prices, marketplaces have no reason to discount fees. Instead, the presence of the anti-discounting policy incentivizes the marketplace to increase fees.”

    The company challenged Pathak’s methodology, arguing that (1) the model Pathak used is not generally accepted in the field of economics; (2) the model has an extraordinary error rate; (3) the model rests upon unreliable and unfounded assumptions; and (4) the model ignores heterogeneity in sellers’ business strategies. Amazon also contended that Pathak’s regression analyses are unreliable because the data sample is too small, and that his regressions do not show a relationship between fees and prices.

    General Acceptance of Economic Model

    Amazon contended that Pathak’s methodology, derived from a 2016 paper by Andre Boik and Kenneth S. Corts, is unreliable because the model used is not widely accepted in the field of economics.

    The company asserted that there are no standards for applying the model beyond simplified assumptions and it does not reflect a generally accepted consensus in the field of economics. 

    The Court held that Pathak’s application of the Boik-Corts model to Amazon’s transactional data did not render his opinion unreliable. After all, Amazon did not point the Court to any economic literature describing flaws or errors in the model. 

    Moreover, Amazon’s contention that Pathak improperly extended the Boik-Corts model to the facts of this case is unavailing. Pathak said that he applied the Boik-Corts model to transactional data provided by Amazon to assess the impact of the company’s anti-discounting policies. He analyzed about 236 million individual items sold on Amazon from May 2017 to July 2023 across 30 different categories.

    In sum, Pathak took a peer-reviewed economic model and applied that model to transactional data provided by Amazon.

    Error Rate

    Amazon asserted that Pathak’s model has a 100% false positive rate because it always concludes that a PMFN is inflating all fees and prices even when analyzing data when no PMFN was in effect.

    In his rebuttal report, Pathak explained that the Boiks-Corts model “is not a test of whether a PMFN exists, and it does not return ‘positive’ or ‘negative’ results.”

    Pathak stated that he reviewed the record, and the facts supported his conclusion that Amazon’s anti-discounting policies constituted a class-wide PMFN.  In his report, Pathak explained the facts that lead him to reach this conclusion.

    That Pathak’s model assumed the existence of a PMFN did not automatically render it unreliable. The Court held that Pathak reviewed the facts and explained his basis for concluding that Amazon’s anti-discounting policies act as a PMFN. Thus, Amazon’s argument did not show that the economic model Pathak used is unreliable. 

    The Model’s Underlying Assumptions

    Amazon asserted that Pathak “assumes without justification” that Amazon’s policies and practices constitute a PMFN. Amazon added that Pathak’s opinion of class-wide injury and damages contains too many assumptions and was not supported by real-world evidence. 

    Pathak evaluated (1) the Price Parity Clause, (2) the Select Competitor Featured Offer Disqualification program, (3) the Marketplace Fair Pricing Provision, (4) Amazon’s Standard for Brands, and (5) the Seller Code of Conduct. He discussed these policies, described how Amazon enforced them, and assessed their impact on merchant and consumer conduct.

    The Court held that Amazon’s contention—that Pathak’s model was unreliable because its underlying assumptions did not reflect reality—was unpersuasive.

    Heterogeneity in Sellers’ Business Practices

    Amazon contended that Pathak’s methodology did not account for “focal point” pricing—i.e., a practice in which sellers commonly set prices ending with certain values such as $0.99. 

    Focal point pricing occurs when retailers set prices at “focal points,” such as prices ending in 99 cents or a round number. 

    Pathak made it clear in his rebuttal report that “The possibility of focal point pricing behavior does not affect [his] conclusion that all or virtually all class members were harmed by the conduct. This is because virtually all class members made enough purchases to have overpaid on at least one of them, even if they were not harmed on purchases of focally-priced items of merchandise.”

    Thus, Pathak accounts for focal point pricing and reasonably explains why focal point pricing does not impact his determinations.

    Reliability of Pathak’s Regressions Analyses

    Amazon contended that Pathak’s regression analyses are unreliable because they rely on a small, unrepresentative data sample.

    Pathak studied how Amazon’s fees affected merchandise prices by analyzing price changes following Amazon’s partial fee reduction in 2019 for four product categories: Baby, Health & Personal Care, Beauty, and Furniture. He stated that the results from his analyses confirmed the model’s predictions: lower fees lead to lower prices. He used a difference-in-difference econometric model to compare the prices of individual goods sold on Amazon to other online marketplaces like Walmart. Pathak said that his analysis “supplements and supports the findings of the economic model.”

    In 2019, Amazon lowered its fees in four categories of products: Baby, Health & Personal Care, Beauty, and Furniture. Pathak said that this change applied to a subset of goods within these categories. He explained that he analyzed these fee changes, separately and collectively, to empirically assess whether the change in fees had an impact on product pricing.

    In his rebuttal report, Pathak emphasized that he did not “cherry-pick subsets of the data.” He said that he “analyzed all available prices in every category where a fee reduction occurred.” 

    Moreover, whether the results are statistically significant is testable. Pathak noted that he tested for statistical significance using measures such as the t-statistic. There is nothing to suggest that Pathak selected the data in a biased manner; instead, he appears to have analyzed all the data available to him. Moreover, the Court held that Pathak performed these regression analyses on available empirical data to corroborate the conclusion of his economic modeling.

    Held

    The Court denied Amazon’s motion to exclude testimony of Dr. Parag A. Pathak, Ph.D.

    Key Takeaway:

    The Daubert inquiry is flexible, and the listed factors do not apply equally to every type of expert testimony. Here, Pathak’s conclusions are capable of being tested. And his opinions “are supported by rational explanations which [a] reasonable [person] might accept, and none of his methods strike the court as novel or extreme.” 

    Case Details:

    Case Caption: De Coster Et Al V. Amazon.Com Inc
    Docket Number: 2:21cv693
    Court Name: United States District Court, Washington Western
    Order Date: July 01, 2025