Doctor Ai LLC v. WebMD LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Doctor Ai LLC (Mississippi)
  • Defendant: WebMD, LLC (California)
  • Plaintiff’s Counsel: Pro Se (Azad Kabir, Founder and Managing Member)
• Case Identification: 4:25-cv-00130, M.D. Ga., 04/21/2025
• Venue Allegations: Venue is alleged to be proper in the Middle District of Georgia because Defendant conducts substantial business in the district and offers its accused "Symptom Checker" tool to residents of Georgia.
• Core Dispute: Plaintiff alleges that Defendant’s "Symptom Checker" tool infringes a patent directed to a method for generating medical diagnoses, and further alleges that Defendant misappropriated Plaintiff's trade secrets to develop the tool.
• Technical Context: The lawsuit concerns the field of computer-implemented diagnostic tools, which use algorithms to analyze patient-reported symptoms and generate a list of potential medical conditions.
• Key Procedural History: The complaint alleges that in 2018, Plaintiff granted a third-party engineering firm, THOUGHTI LLC, access to its proprietary database under a non-disclosure agreement. Plaintiff further alleges that Defendant subsequently gained unauthorized access to this database through THOUGHTI LLC and used it to enhance the accused "Symptom Checker" tool. These allegations connect the trade secret claim to the patent infringement claim by asserting a common factual basis for the development of the accused technology.

Case Timeline

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 11,972,865 - High Probability Differential Diagnoses Generator And Smart Electronic Medical Record

The patent-in-suit is U.S. Patent No. 11,972,865, issued April 30, 2024 (’865 Patent).

The Invention Explained

• Problem Addressed: The patent addresses the inefficiency and potential for error in medical diagnostic processes, noting that physicians, particularly novices, struggle to quickly generate and correctly prioritize potential diagnoses (hypotheses) early in a patient encounter. It also identifies a failure of existing electronic medical records (EMRs) to effectively aid in this diagnostic decision-making process (ʼ865 Patent, col. 2:23-41).
• The Patented Solution: The invention is a computer-implemented method that receives multiple patient signs and symptoms, compares them against a medical database, and generates a ranked list of potential diagnoses. The core of the solution is a specific ranking methodology that first prioritizes diseases based on how many of the input symptoms they are associated with, and then further sorts them based on a pre-determined epidemiological ranking (ʼ865 Patent, col. 9:8-25; FIG. 3). This is intended to produce a clinically meaningful short list of high-probability diagnoses for the healthcare provider (ʼ865 Patent, col. 6:26-34).
• Technical Importance: The described method aims to systematize and improve the speed and accuracy of differential diagnosis, potentially reducing diagnostic errors and unnecessary healthcare costs (ʼ865 Patent, col. 2:48-59).

Key Claims at a Glance

• The complaint does not specify which claims are asserted. The following analysis focuses on representative independent claim 1.
• Independent Claim 1 (Method):
  • collecting a first and second medical clinical data from a patient;
  • linking the collected data with a differential diagnosis medical database;
  • comparing the collected data to the database to isolate disease data common to the first data and, separately, the second data;
  • isolating disease data common to both the first and second data groupings; and
  • ranking the common disease data into a third ranked list, where the position is based on (1) "the number of times said disease data is associated with" the collected data, followed by (2) "the relative ranked position" of the disease data associated with the first collected data.

III. The Accused Instrumentality

Product Identification

Defendant's "Symptom Checker" tool (Compl. ¶ II.3).

Functionality and Market Context

The complaint alleges that the "Symptom Checker" is a software tool offered to residents of Georgia that generates differential diagnoses based on patient symptoms (Compl. ¶ II.3, III.1). Plaintiff alleges the tool is a source of revenue for Defendant by driving traffic to its platform (Compl. ¶ III.6). The complaint further alleges that the functionality of the accused tool was enhanced through the unlawful use of Plaintiff's proprietary database, which was allegedly obtained via the third-party firm THOUGHTI LLC (Compl. ¶ III.5).

IV. Analysis of Infringement Allegations

The complaint does not contain a claim chart or provide specific technical details about the operation of the accused "Symptom Checker" tool. The following chart maps the general allegations to the elements of representative Claim 1.

’865 Patent Infringement Allegations

• Identified Points of Contention:
  • Technical Questions: A primary factual dispute will be whether Plaintiff can produce evidence that the "Sympton Checker" actually performs the specific two-part ranking method required by Claim 1. The complaint makes a conclusory allegation of infringement but does not describe how the accused tool ranks its diagnostic outputs. The case may depend on whether discovery reveals that the accused tool's algorithm performs a function that meets the "number of times... followed by the relative ranked position" limitation.
  • Scope Questions: The dispute may raise the question of whether the general process of generating a list of possible conditions based on symptoms, a common feature of many online health tools, is sufficient to meet the specific "comparing," "isolating," and "ranking" steps of the claim.

V. Key Claim Terms for Construction

• The Term: "ranking... wherein the position... is based upon: the number of times said disease data is associated with said first medical data and said second medical data followed by the relative ranked position of said isolated disease data associated with said first medical data"

• Context and Importance: This lengthy limitation describes the core algorithmic step of the invention. Its construction will be dispositive for infringement. Practitioners may focus on this term because the infringement analysis will turn on whether the accused tool's algorithm matches this specific, two-factor sequential logic.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: A party might argue that the plain language does not require a rigid, multi-pass sorting process and could cover any ranking system that considers both the quantity of symptom matches and some form of pre-existing disease priority.
  • Evidence for a Narrower Interpretation: The specification provides a highly detailed example of this ranking process, explaining how diseases are first sorted by the number of matching symptoms (e.g., a disease matching three symptoms is ranked above one matching two), and only then are ties broken by a pre-existing order (ʼ865 Patent, col. 11:40-12:44). A party could argue this detailed embodiment defines the required sequence and limits the claim to that specific algorithm.

• The Term: "medical clinical data"

• Context and Importance: The scope of this term determines the type of information the claimed method must process. Its construction is important because if it is construed narrowly to require formal clinical findings, a public-facing tool that only accepts user-reported symptoms might not infringe.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The patent frequently uses the term interchangeably with "signs, symptoms, or clinical findings (SSF)," suggesting it could encompass any information a patient provides (ʼ865 Patent, col. 6:39-41).
  • Evidence for a Narrower Interpretation: The specification also provides examples that include "laboratory data, radiological data, vital signs" as inputs, which could support an argument that "medical clinical data" requires more than just self-reported symptoms (ʼ865 Patent, col. 8:45-48).

VI. Other Allegations

• Indirect Infringement: The complaint does not contain allegations of indirect infringement (inducement or contributory infringement). It focuses on Defendant's direct infringement through the operation of its "Symptom Checker" tool.
• Willful Infringement: The complaint alleges that Defendant's infringement is "willful and intentional" (Compl. ¶ IV.3). The factual basis appears to be the allegation that Defendant knowingly misappropriated Plaintiff's proprietary database via a third party in 2018-2020 (Compl. ¶ III.3-5). This raises a question of timing, as the alleged conduct underlying the willfulness claim occurred years before the ’865 patent issued in 2024.

VII. Analyst’s Conclusion: Key Questions for the Case

• A key evidentiary question will be one of algorithmic operation: can Plaintiff demonstrate, through discovery, that Defendant’s "Symptom Checker" performs the specific, two-part ranking methodology recited in Claim 1? The complaint's current lack of factual detail on this point makes it a central vulnerability that will need to be addressed with evidence.
• The case will likely turn on a question of claim scope: will the court construe the "ranking" limitation narrowly to require the exact sequential logic described in the patent's preferred embodiment, or more broadly to cover other weighted ranking systems? The outcome of this construction will likely determine infringement.
• A third critical issue involves the intersection of patent and trade secret law: how will the court treat evidence of the alleged trade secret misappropriation, which occurred pre-patent issuance, in assessing claims of post-issuance willful patent infringement? The connection between the allegedly stolen "database" and the patented "method" will be a central theme of the litigation.