How Do You Prove You Used Roundup?

If you’ve been diagnosed with cancer, such as non-Hodgkin lymphoma, after using Roundup, you may be eligible to file a lawsuit against Bayer, the manufacturer of this widely used herbicide. However, succeeding in a Roundup lawsuit requires robust evidence to prove your exposure to Roundup’s active ingredient, glyphosate, and its link to your health condition. This guide explains how to prove you used Roundup, detailing the types of evidence needed, practical tips for gathering it, and why each piece matters. Whether you’re a farmer, landscaper, or homeowner, this article will help you understand the process and strengthen your case.

Why Proving Roundup Use Is Critical

Roundup lawsuits hinge on demonstrating three key elements:

1. You were exposed to Roundup. 
2. You developed a qualifying cancer, and 
3. Your exposure caused or contributed to your illness. 

Bayer and Monsanto, the original manufacturer, often contest claims by arguing insufficient exposure or lack of causation. Strong evidence is essential to counter these defenses and secure compensation for medical bills, lost wages, and pain and suffering. As of July 2025, over 170,000 lawsuits have been filed, with Bayer paying out nearly $11 billion in settlements, highlighting the importance of solid proof.

Types of Evidence to Prove Roundup Use

To build a compelling case, you’ll need to gather multiple forms of evidence. Below are the primary categories, with practical tips for obtaining them.

1. Proof of Purchase or Ownership

Demonstrating that you purchased or owned Roundup products is a cornerstone of proving exposure.

• Receipts or Invoices: Keep receipts from retailers like Home Depot, Walmart, or Amazon showing purchases of Roundup or glyphosate-based products. Digital purchase histories from online accounts can also serve as proof.
• Partially Used or Unopened Containers: Retain any Roundup containers, even if empty, as they can verify the product and its glyphosate content. Photograph the containers with batch numbers or labels for documentation.
• Tips for Homeowners: If you’ve lost receipts, check credit card statements, loyalty program records, or email confirmations for purchase evidence. Ask neighbors or family members if they recall you buying or using Roundup.

Tips: For those who may not have receipts, consider checking with local hardware stores or garden centers where you may have purchased the product, as they may have records of your transactions.

2. Employment Records

If you used Roundup as part of your job, employment records can substantiate your exposure.

• Job Descriptions: Provide records showing your role involved herbicide use, such as landscaping, farming, or groundskeeping duties.
• Incident Reports: Submit any workplace reports documenting Roundup use or exposure incidents.
• Pay Stubs or Contracts: These can verify your employment in industries with high glyphosate exposure, such as agriculture or lawn care.
• Tips: Request records from former employers or HR departments. If unavailable, coworker or supervisor statements can corroborate your exposure.

3. Witness Testimony

Testimony from others who saw you use Roundup can strengthen your case.

• Coworkers or Supervisors: Colleagues who worked with you can confirm your use of Roundup on the job.
• Family or Neighbors: For residential users, statements from those who saw you spraying Roundup at home can help.
• Tips: Collect written or notarized statements detailing the frequency and context of your Roundup use. Your attorney can assist with formalizing these statements.

4. Medical Records

Medical records are crucial to prove your cancer diagnosis and link it to Roundup exposure.

• Diagnosis Documentation: Obtain records confirming a qualifying cancer, such as non-Hodgkin lymphoma, multiple myeloma, or leukemia, diagnosed at least two years after Roundup exposure.
• Treatment Records: Include details of chemotherapy, radiation, or surgeries to demonstrate the impact of your illness.
• Exposure Notes: If your doctor noted Roundup use during examinations, this can support your claim.
• Tips: Request copies of your medical records from your healthcare provider or hospital. Ensure they include histopathology reports and treatment details.

5. Expert Testimony

Expert witnesses can establish a scientific link between Roundup and your cancer.

• Toxicologists: Experts can explain how glyphosate affects the body, citing studies like the 2019 meta-analysis showing a 41% increased risk of non-Hodgkin lymphoma from glyphosate exposure.
• Oncologists: Medical professionals can connect your diagnosis to Roundup exposure.
• Epidemiologists: They can discuss the likelihood of cancer from glyphosate exposure based on population studies.
• Tips: Your attorney will typically arrange expert testimony, but you can suggest relevant specialists, such as your treating oncologist.

6. Scientific Studies

Scientific evidence strengthens causation arguments.

• Key Studies: Reference studies like the International Agency for Research on Cancer’s (IARC) 2015 classification of glyphosate as a “probable human carcinogen” or the 2023 systematic review of 175 studies supporting this finding.
• Tips: Your attorney can compile relevant studies, but reviewing sources like ScienceDirect or PubMed can help you understand the science behind your claim.

Challenges and Solutions

• Missing Receipts: If you lack purchase records, rely on employment records, witness testimony, or photos of Roundup containers. Check old bank statements or retailer records.
• Non-Occupational Users: Homeowners may struggle to prove exposure. Use neighbor testimony, photos, or records of lawn care services that used Roundup.
• Statute of Limitations: Most states require filing within 1-6 years of diagnosis or discovery of the Roundup-cancer link. Act quickly to avoid missing deadlines.
• Bayer’s Defenses: Bayer may argue insufficient exposure or alternative causes. Comprehensive evidence and expert testimony can counter these claims.

Timeline of Roundup Litigation

• 1974: Roundup was introduced by Monsanto.
• 2015: IARC classifies glyphosate as a probable carcinogen.
• 2018: Bayer acquires Monsanto; lawsuits surge after $289 million verdict in Dewayne Johnson case.
• 2020: Bayer settles ~100,000 claims for $10.9 billion.
• 2023-2025: Over 58,000 claims remain active, with verdicts like $2.25 billion in Philadelphia (2024).

Tips for Gathering Evidence

1. Act Promptly: Start collecting evidence immediately after diagnosis to meet statute of limitations deadlines.
2. Organize Records: Create a file with receipts, medical records, and employment documents.
3. Consult an Attorney Early: An experienced Roundup lawyer can guide evidence collection and arrange expert testimony.
4. Document Exposure Details: Note the frequency, duration, and method of Roundup use (e.g., spraying, mixing).
5. Preserve Physical Evidence: Keep Roundup containers and avoid discarding relevant items.

Why Choose an Experienced Attorney?

Navigating a Roundup lawsuit is a complex process, requiring rigorous evidence and specialized legal expertise. An attorney can:

• Gather and authenticate evidence.
• Hire expert witnesses to establish causation.
• Counter Bayer’s legal defenses.
• Ensure compliance with state-specific deadlines.

Frequently Asked Questions

What cancers qualify for a Roundup lawsuit?
Non-Hodgkin lymphoma, multiple myeloma, leukemia, and certain B-cell lymphomas are commonly linked to glyphosate exposure. Consult an attorney to confirm eligibility.

How long do I have to file a lawsuit?
Statutes of limitations vary by state (1-6 years from diagnosis or discovery). Contact a lawyer immediately to avoid missing deadlines.

What if I don’t have receipts?
Use employment records, witness testimony, photos, or credit card statements to prove exposure. Your attorney can help locate additional evidence.

How much compensation can I expect?
Settlements typically range from $5,000 to $250,000, averaging $150,000, depending on case strength and damages.

Can I file if a loved one passed away?
Yes, family members may file wrongful death lawsuits if the deceased used Roundup and developed a qualifying cancer.

Take Action Today

If you or a loved one developed cancer after using Roundup, you may be entitled to compensation. Proving your case requires careful evidence collection, but with the right legal support, you can hold Bayer accountable. Contact Clinton O. Middleton, Attorney at Law, at (703) 777-9630 or fill out our online form for a free case review to start building your case today.

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