Expert Witness Profiler

Category: Computer Science Expert Witness

  • Computer Science Expert Was Allowed to Opine on Minting Activity

    Computer Science Expert Was Allowed to Opine on Minting Activity

    Plaintiff Trenton Smith brought claims against Defendant Nelk, Inc. doing business as Nelk or Full Send, Defendant Nelk USA, Inc., Defendant Metacard LLC, Defendant Kyle Forgeard (“Kyle”), and Defendant John Shahidi (“John”) (collectively, “Defendants”) related to Plaintiff’s Metacard purchases.

    Smith alleged that Defendants made promises regarding the benefits of owning a the Metacard NFT (“Metacard”) that Defendants had no intention of delivering. These benefits were included both long-term investment value and ongoing “perks.”

    The ongoing perks described by Defendants included gym memberships, exclusive events and first access to new projects launched by Defendants. Defendants made these promises to induce individuals, particularly Defendants’ fan base, to purchase the Metacard, all while knowing they would not fulfill those promises and fully intending to enrich themselves. Plaintiff and the Class Members relied on Defendants’ representations in purchasing the Metacard, earning Defendants approximately $23 million in initial sales plus another approximately $4.3 million in royalties on re-sales.

    Defendants filed a motion to exclude the opinions of Jeremy Clark pursuant to Federal Rule of Evidence 702. 

    Computer Science Expert Witness

    Jeremy Clark is an associate professor at the Concordia Institute for Information Systems Engineering at Concordia University in Montreal, Canada. From 2019 to 2025, Clark held the National Sciences and Engineering Research Council of Canada/Raymond Chabot Grant Thornton/Catallaxy Industrial Research Chair in Blockchain Technologies.

    Clark holds a Ph.D. in Computer Science from the University of Waterloo, awarded in 2011, and he is a professional engineer with the Professional Engineers of Ontario. He has a decade of research expertise in digital assets (e.g., Bitcoin and Ethereum), blockchain, and related areas of cryptography, and 20 peer-reviewed papers on Bitcoin, Ethereum, digital assets, and blockchain technology.

    Clark has also testified on digital assets to the Standing Senate Committee on Banking, Commerce and Economy of the Senate of Canada, and to the Standing Committee on Finance of the House of Commons of Canada. Additionally, Clark has given over 50 presentations on digital assets to companies, government agencies, law enforcement, pension plans, and academic groups.

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

    Discussion by the Court

    Defendants argued (1) that Clark failed to articulate a reliable methodology, and (2) that he is unqualified.

    First, the parties dispute whether Clark’s methodology is vague and underdeveloped. The Court found that Clark’s testimony was the product of sufficiently reliable principles because he explained the Mint process, how the Metacards were created and assigned to the original owners, and the unique addresses that purchased the Metacards.

    Clark began his review of the blockchain activity associated with the Metacard by examining “archives of websites affiliated with the NFT with the Internet Archive.” Clark relied on datasets curated and offered through the Dune Analytics tool, finding data about Metacard’s minting activity. 

    According to Clark, “minting is the Ethereum-based activity of creating the new token ID and assigning it to the owner’s address,” and the “address of the entity that created the NFT collection [here] is 0x9E . . . C731” (the “Metacard treasury”).

    And using this information, Clark can estimate the number of Metacard purchasers based on the number of unique Ethereum addresses that held a Metacard at some point, can trace the flow of funds between addresses related to these transactions, can separate out secondary sales following the Mint, and can trace royalties earned from Metacard transfers. For example, Clark described the transfer history of the Metacard treasury which deployed the NFT collection, the Ethereum flowing out of this address, and its eventual depletion.

    Second, Defendants argued that Clark lacked the qualifications to opine on class-wide damages. However, the Court found that Clark had sufficient experience with digital assets to offer his opinions.

    Held

    The Court denied Defendants’ motion to exclude the opinions of Jeremy Clark.

    Key Takeaway

    Clark’s explanation of the steps in his methodology, breakdown of his analysis, and description of the data he relies on provided sufficient assurance to the Court in its gatekeeping capacity that exclusion is not necessary on the basis of unreliable methods.

    Case Details:

    Case Caption: Trenton Smith V. John Shahidi
    Docket Number: 8:25cv161
    Court Name: United States District Court for the Central District of California
    Order Date: March 09, 2026
  • Computer Science Expert’s Testimony on the Value of Data Admitted

    Computer Science Expert’s Testimony on the Value of Data Admitted

    This class action lawsuit arises out of Amazon’s practice of using smart-speaker technology (“Alexa”) to surreptitiously: (a) intercept; (b) eavesdrop; (c) record; (d) disclose; or (e) use millions of Americans’ voices and communications, all without their knowledge or consent. Such conduct blatantly violates Washington’s wiretapping law, which applies nationwide to Plaintiffs and all members of the Class.

    Defendants here, Amazon.com, Inc. and Amazon.com Services LLC (collectively, “Amazon” or “Defendants”), are therefore liable as a result of their egregious violations of the State Wiretapping laws – and are also liable for their violations of the Washington Consumer Protection Act (“CPA”), the Electronic Communications Privacy Act of 1986 (“Federal Wiretap Act”), and the Stored Communications Act of 1986 (“SCA”). Plaintiffs Kaeli Garner, Jodi Brust, Diane McNealy, Michael McNealy, Ricky Babani, Jeffrey Hoyt, Lorlie Tesoriero, Ronald Johnson, Selena Johnson and Caron Watkins (collectively, “Plaintiffs”) brought this action individually, and on behalf of a Class of similarly situated individuals, to redress those violations of law.

    Amazon filed a motion to exclude the testimony of Plaintiffs’ expert Jonathan Hochman. Defendants sought to exclude Hochman’s testimony that (a) a large collection of utterances or speech data has value and can be utilized for various purposes, (b) each individual user’s data has discrete value in and of itself, and (c) Amazon could have programmed Alexa to record only the voices of registered users.

    Computer Science Expert Witness

    Jonathan E. Hochman, PhD. has 35 years of experience in software product development, internet technology, online marketing, and cybersecurity. He is a Yale University graduate with four degrees in computer science. He currently teaches classes on computer privacy and is conducting research related to computer security, privacy, and distributed computing.

    Between stints as a student, Hochman founded companies aimed at assisting clients with internet marketing and internet security, developing secure and private user authentication options, and integrating systems to maximize data capture and efficiency. He has also served as an expert regarding online data collection practices, software development, marketing, e-commerce, and internet security. His most recent article and research involve the tension between maintaining large data repositories for machine learning and safe-guarding individual privacy.

    Fortify your strategy by reviewing a Challenge Study detailing grounds for excluding Jonathan Hochman’s expert testimony.

    Discussion by the Court

    A. Knowledge and Expertise

    Amazon argued that Hochman’s admitted expertise in amassing, handling, using, and analyzing data is not transferrable to this case because his experiences involved types of data other than voice data. The distinction is unexplained and is unclear in this context. The challenged testimony is being offered to show the ways in which large quantities of data are used to train and improve products (such as the Alexa device), to explain the means by which Amazon and other market participants value the data they use for such purposes, and to provide a basis for the jury to conclude that consumers have been injured by Amazon’s collection of the data. Whether that data is in the form of a key stroke or an utterance is not dispositive of the relevant legal analysis.

    Amazon also argued that Hochman lacks training and/or experience in economics and is therefore unable to assign a value to the data Amazon collects and uses. Hochman has not, however, offered an opinion regarding the actual value of the voice recordings at issue, either individually or en masse.

    Finally, Amazon objected to the opinions set forth in Section D.i. of Mr. Hochman’s report, namely that “it is technologically feasible for products to not record a voice that is not registered or recognized.” This opinion is based on Hochman’s interpretation of internal Amazon documents, his understanding of how Apple’s Siri virtual assistant works, and his work experiences with internet user authentication and identification through voice prints. The fact that he has not developed or created a voice print authentication system does not prevent him from opining that such a thing exists.

    B. Helpfulness

    Amazon argued that (1) proof that voice data has value to Amazon is insufficient to prove that Alexa customers were injured by Amazon’s taking of the data and (2) even if the collection and use of the data caused injury, Hochman has not proposed a damages model capable of measuring or calculating damages in the absence of individualized proof.

    Amazon does not dispute that it has a need for and values the voice recording data it collects. Before Alexa was capable of collecting the necessary utterances — i.e., before the product was fully deployed and in homes across the country — Amazon paid people to generate and contribute their audio data. Once Alexa became operational, however, Amazon opted to take, store, and use the utterances recorded by the system rather than pay users for that privilege. A reasonable fact finder could conclude that Amazon’s allegedly unfair acts deprived Alexa users of the opportunity to sell their voice data, thereby giving rise to an “injury to property” commensurate with the value of the taken data.

    While the collected data undoubtedly has a higher value to Amazon than it does to individual Alexa users, Hochman’s testimony is sufficient to allow the fact finder to conclude that, had Amazon not simply taken the voice recordings, a mutually agreeable price for the data could have been reached and the users were deprived of that value.

    Moreover, Hochman offers at least two common methods for establishing the value of the voice data Amazon took and used for its own purposes without compensation, namely (a) the fair market value of individual utterances or monthly subscriptions for the data and (b) the costs Amazon is incurring or has incurred to acquire non-Alexa voice recordings. 

    C. Regurgitation of Documents

    Amazon asserted that “most of Opinions 3 and 4” consisted of nothing more than quotations from Amazon’s documents and/or that the quoted documents require no expertise to understand and apply in this case.

    Amazon made no attempt to explain why Hochman should be precluded from relying on Amazon’s documents to support his opinions that the utterances Amazon has collected, individually and as a collective, have value.

    Held

    The Court denied the Defendants’ Daubert motion to exclude the testimony of Jonathan Hochman.

    Key Takeaway

    Hochman used his experience, education, and selected resources (including Amazon’s documents) to define the terms of art used in this litigation, to explain how Alexa works and improves with both positive and negative training data, to show why the data Amazon has been collecting has value, and to identify various choices Amazon made in furtherance of its efforts to collect voice data regardless of user privacy interests.

    Case Details:

    Case Caption: Garner V. Amazon.Com, Inc.
    Docket Number: 2:21cv750
    Court Name: United States District Court for the Western District of Washington
    Order Date: January 05, 2026
  • Computer Science Expert Witness’ Testimony About the Disclosure of App Users’ Email Addresses Admitted

    Computer Science Expert Witness’ Testimony About the Disclosure of App Users’ Email Addresses Admitted

    In this putative class action, Plaintiff Charles Therrien claimed that Defendant Hearst Television, Inc. (HTV or Hearst), unlawfully disclosed his personally identifiable information – including a record of every video he had viewed on Hearst’s Apps – to two third parties, Braze and Google, in violation of the Video Privacy Protection Act.

    HTV argued that its news and weather apps share only specific data with its vendors, Braze and Google Ad Manager (“GAM”), limited by each user’s
    permissions. None of those data points identify a specific person as having requested a specific, prerecorded video. HTV’s separate video identifier value is never shared. Nor is there any evidence that HTV knew that the data it did share could identify a user, let alone connect a user to specific video content, as required to be deemed personally identifying information under the Video Privacy Protection Act.

    Hearst filed a motion to strike the expert testimony of Dr. Narseo Vallina-Rodriguez for all purposes pursuant to Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 113 S. Ct. 2786, 125 L. Ed. 2d 469 (1993). Hearst also moved to strike the allegedly untimely expert report of Dr. Jason Polakis.

    Computer Science Expert Witnesses

    Narseo Vallina-Rodriguez has considerable experience in the fields of mobile platforms and application analysis, computer network analysis and measurement, and mobile privacy and security risks. His 15-year career in these fields includes his work at the International Computer Science Institute at University of California, Berkeley, analyzing mobile applications’ privacy and security practices, and his work at AppCensus Inc., analyzing Android users’ geolocation data and unique identifiers – along with his education – which includes a M.Sc. in Telecommunications Engineering from the University of Ovideo and a PhD in Computer Science from the University of Cambridge.

    Get the full story on challenges to Narseo Vallina-Rodriguez’s expert opinions and testimony with an in-depth Challenge Study. 

    Jason Polakis has focused on understanding the security and privacy limitations of Internet technologies and mobile systems, and designing fully automated auditing frameworks and robust defenses. His work has revealed significant flaws in popular web services and browsers, and major vendors have deployed his proposed defenses, leading to concrete security and privacy benefits for billions of users.

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

    Discussion by the Court

    In Ruiz-Troche v. Pepsi Cola of Puerto Rico Bottling Co., 161 F.3d 77, 85 (1st Cir. 1998), it was held that “Daubert does not require that a party who proffers expert testimony carry the burden of proving to the judge that the expert’s assessment of the situation is correct . . . . In short, Daubert neither requires nor empowers trial courts to determine which of several competing theories has the best provenance. It demands only that the proponent of the evidence show that the expert’s conclusion has been arrived at in a scientifically sound and methodologically reliable fashion.”

    Narseo Vallina-Rodriguez

    To begin with, Hearst argued that Vallina-Rodriguez’s testimony should be stricken as it is based on an unreliable methodology.

    In forming his opinion that the disclosure of App users’ email addresses, geolocation, and AAIDs (Mobile Advertising IDs) was reasonably and foreseeably likely to reveal their identities to Braze and Google, the Court held that Vallina-Rodriguez relied on a systematic literature survey of various peer-reviewed empirical studies that include data aggregations similar to those in this case, e.g., timestamped geolocation data points collected by GPS sensors on cell phones.

    The idea that individuals are likely to be identified and de-anonymized by cross-referencing external data sources against frequented locations is a conclusion accepted within the data privacy research community.

    Although, as HTV points out, Vallina-Rodriguez has not conducted an empirical analysis involving Therrien personally, he was given access to only a single datapoint, which was the last known geolocation coordinate of Therrien. Moreover, Vallina-Rodriguez did not analyze the 78 points of geolocation data for former named Plaintiff Michele Saunders because he was not attempting to identify her.

    The Court held that Hearst’s challenges to Vallina-Rodriguez’s testimony, at best, addressed the weight of the evidence as opposed to its admissibility. To the extent Vallina-Rodriguez’s opinions constitute legal conclusions or are based on insufficient anecdotal evidence, they may be subject to a proper motion in limine or appropriate objection at trial. 

    Jason Polakis

    When considering whether to strike an untimely expert report, the Court may consider various factors: (1) the history of the litigation; (2) the sanctioned party’s need for the precluded evidence; (3) the sanctioned party’s justification (or lack of one) for its late disclosure; (4) the opponent-party’s ability to overcome the late disclosure’s adverse effects (e.g., the surprise and prejudice associated with the late disclosure); and (5) the late disclosure’s impact on the district court’s docket.

    On Friday, December 6, 2024 at 5:31 pm, Plaintiffs’ counsel emailed Hearst’s counsel an expert report from Polakis, who had not previously been identified by the Plaintiff.

    The scheduling order entered by the Court in this case made it clear, as recently as May 0f 2024, that Plaintiff’s expert reports were due on October 18, 2024, and that all expert discovery was to be completed by December 6, 2024. 

    However, Therrien failed to disclose Polakis or his expert report within this Court’s discovery deadlines and offered no reason as to why he could not have identified him earlier and provided his report in a timely manner. In other words, the Court did not accept Therrien’s lame characterization of the report as a “rebuttal” and made particular note of the fact that there was no effort on Plaintiff’s part to seek an amendment extending the Court’s discovery schedule and its deadlines. 

    Moreover, Rule 26 provides a schedule for a rebuttal report only in the absence of a scheduling order (which is not the case here).

    In conclusion, to permit Therrien to ambush the Defendant with a previously undisclosed expert report of a previously unidentified witness would “undermine the purpose of setting deadlines for expert disclosures; those deadlines must have some force if the courts are to be able to manage their dockets in any meaningful way.” 

    Held

    The Court denied Hearst’s motion to strike the testimony of Dr. Narseo Vallina-Rodriguez but allowed the motion to strike the report of Dr. Jason Polakis.

    Key Takeaway:

    • Vallina-Rodriguez’s testimony was based on a reliable methodology because he relied on a systematic literature survey of various peer-reviewed empirical studies that include data aggregations similar to those in this case, e.g., timestamped geolocation data points collected by GPS sensors on cell phones.
    • Therrien failed to disclose Polakis or his expert report within this Court’s discovery deadlines and offered no reason as to why he could not have identified him earlier and provided his report in a timely manner. The Court did not accept Therrien’s lame characterization of the report as a “rebuttal” and made particular note of the fact that there was no effort on Plaintiff’s part to seek an amendment extending the Court’s discovery schedule and its deadlines. 

    Case Details:

    Case Caption: Therrien V. Hearst Television
    Docket Number: 1:23cv10998
    Court: United States District Court, Massachusetts
    Order Date: February 14, 2025