EXPERT WITNESS SUPPLEMENTAL REPORT

Case Information

Case Caption: [________________________________]

Case Number: [________________________________]

Court: [________________________________]

Jurisdiction: [________________________________]

Retaining Party: ☐ Plaintiff ☐ Defendant ☐ Other: [________________]

Retaining Counsel:
- Name: [________________________________]
- Firm: [________________________________]
- Address: [________________________________]
- Phone: [________________________________]
- Email: [________________________________]

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Expert Identification

Expert Name: [________________________________]

Professional Title: [________________________________]

Business Address: [________________________________]

Phone: [________________________________]

Email: [________________________________]

Field of Expertise: [________________________________]

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Original Report Information

Date of Original Report: [__/__/____]

Date of Expert Deposition (if taken): [__/__/____]

Date of Any Prior Supplemental Reports: [__/__/____]

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I. Purpose of Supplemental Report

This supplemental report is prepared pursuant to Federal Rule of Civil Procedure 26(e), which requires a party to supplement or correct expert disclosures in a timely manner if the party learns that the disclosure is incomplete or incorrect in some material respect.

A. Reason for Supplementation

☐ New information has become available since the original report
☐ Additional documents have been produced in discovery
☐ Additional depositions have been taken
☐ Correction of error in original report
☐ Clarification of opinions stated in original report
☐ Response to information learned during expert's deposition
☐ Additional testing or analysis has been completed
☐ Other: [________________________________]

B. Timeliness Certification

☐ This supplemental report is being served within the time required by the court's scheduling order
☐ This supplemental report is being served before pretrial disclosures are due under Rule 26(a)(3)
☐ This supplemental report is being served with special promptness as the trial date approaches

Trial Date: [__/__/____]

Pretrial Disclosure Deadline: [__/__/____]

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II. Summary of Supplementation

A. Opinions Being Supplemented or Corrected

Original Opinion	Nature of Change	Reference in Original Report
[________________]	☐ Supplemented ☐ Corrected	Page [____], Section [____]
[________________]	☐ Supplemented ☐ Corrected	Page [____], Section [____]
[________________]	☐ Supplemented ☐ Corrected	Page [____], Section [____]
[________________]	☐ Supplemented ☐ Corrected	Page [____], Section [____]

B. New Opinions (If Any)

☐ No new opinions are offered in this supplemental report
☐ New opinions are offered based on newly available information

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III. New or Additional Materials Considered

A. Documents

Document	Date Received	Bates Numbers (if applicable)	Relevance
[________________]	[__/__/____]	[________________]	[________________]
[________________]	[__/__/____]	[________________]	[________________]
[________________]	[__/__/____]	[________________]	[________________]
[________________]	[__/__/____]	[________________]	[________________]
[________________]	[__/__/____]	[________________]	[________________]

B. Deposition Testimony

Deponent	Date of Deposition	Relevant Testimony
[________________]	[__/__/____]	[________________]
[________________]	[__/__/____]	[________________]
[________________]	[__/__/____]	[________________]

C. Physical Evidence or Testing

Item	Date Examined/Tested	Analysis Performed
[________________]	[__/__/____]	[________________]
[________________]	[__/__/____]	[________________]

D. Other Information

[________________________________]
[________________________________]
[________________________________]

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IV. Detailed Supplementation

A. Supplementation to Opinion 1

Original Opinion (as stated in original report):
[________________________________]
[________________________________]
[________________________________]

New Information Considered:
[________________________________]
[________________________________]
[________________________________]

Supplemented/Corrected Opinion:
[________________________________]
[________________________________]
[________________________________]

Explanation of Change:
[________________________________]
[________________________________]
[________________________________]

Impact on Overall Conclusions:
☐ No change to overall conclusions
☐ Strengthens original conclusions
☐ Modifies original conclusions as follows: [________________________________]

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B. Supplementation to Opinion 2

Original Opinion (as stated in original report):
[________________________________]
[________________________________]
[________________________________]

New Information Considered:
[________________________________]
[________________________________]
[________________________________]

Supplemented/Corrected Opinion:
[________________________________]
[________________________________]
[________________________________]

Explanation of Change:
[________________________________]
[________________________________]
[________________________________]

Impact on Overall Conclusions:
☐ No change to overall conclusions
☐ Strengthens original conclusions
☐ Modifies original conclusions as follows: [________________________________]

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C. Supplementation to Opinion 3

Original Opinion (as stated in original report):
[________________________________]
[________________________________]
[________________________________]

New Information Considered:
[________________________________]
[________________________________]
[________________________________]

Supplemented/Corrected Opinion:
[________________________________]
[________________________________]
[________________________________]

Explanation of Change:
[________________________________]
[________________________________]
[________________________________]

Impact on Overall Conclusions:
☐ No change to overall conclusions
☐ Strengthens original conclusions
☐ Modifies original conclusions as follows: [________________________________]

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D. Additional Supplementations (As Needed)

[________________________________]
[________________________________]
[________________________________]

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V. Corrections to Original Report

A. Factual Corrections

Page/Section	Original Statement	Corrected Statement	Reason for Correction
[____]	[________________]	[________________]	[________________]
[____]	[________________]	[________________]	[________________]
[____]	[________________]	[________________]	[________________]

B. Typographical/Clerical Corrections

Page/Section	Error	Correction
[____]	[________________]	[________________]
[____]	[________________]	[________________]

C. Methodology Clarifications

[________________________________]
[________________________________]
[________________________________]

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VI. Deposition Testimony Clarifications

If this supplemental report addresses information provided during the expert's deposition:

Deposition Date: [__/__/____]

A. Testimony Requiring Clarification

Page:Line	Original Testimony	Clarification
[____]:[____]	[________________]	[________________]
[____]:[____]	[________________]	[________________]
[____]:[____]	[________________]	[________________]

B. Additional Information Since Deposition

[________________________________]
[________________________________]
[________________________________]

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VII. Additional Testing or Analysis

A. Description of Additional Work

☐ Additional testing performed
☐ Additional calculations performed
☐ Additional research conducted
☐ Additional site inspection
☐ Other: [________________________________]

B. Methodology

[________________________________]
[________________________________]
[________________________________]

C. Results

[________________________________]
[________________________________]
[________________________________]

D. Impact on Original Opinions

[________________________________]
[________________________________]
[________________________________]

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VIII. Updated Conclusions

Based on the supplemental information reviewed and analysis performed, my updated conclusions are:

A. Conclusions That Remain Unchanged

☐ Conclusion 1: [________________________________]
☐ Conclusion 2: [________________________________]
☐ Conclusion 3: [________________________________]

B. Modified Conclusions

Original Conclusion	Modified Conclusion
[________________]	[________________]
[________________]	[________________]

C. New Conclusions (If Applicable)

[________________________________]
[________________________________]
[________________________________]

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IX. Updated Exhibits

A. New Exhibits

Exhibit	Description
Exhibit [____]	[________________________________]
Exhibit [____]	[________________________________]
Exhibit [____]	[________________________________]

B. Revised Exhibits (Replacing Original Exhibits)

Original Exhibit	Revised Exhibit	Description of Revisions
[____]	[____]	[________________________________]
[____]	[____]	[________________________________]

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X. Qualifications Update

☐ No changes to qualifications since original report
☐ Updated qualifications attached (changes highlighted)

Updates since original report:
[________________________________]
[________________________________]

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XI. Prior Testimony Update

Cases in which I have testified as an expert since the original report:

Case Name	Court	Date	Subject Matter
[________________]	[________________]	[__/__/____]	[________________]
[________________]	[________________]	[__/__/____]	[________________]

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XII. Compensation Update

☐ No change to compensation terms since original report
☐ Updated compensation: $[________] per hour

Total compensation to date: $[________]
Estimated additional compensation: $[________]

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XIII. Certification

I hereby certify that:

☐ This supplemental report corrects or supplements material information as required by FRCP 26(e)
☐ This supplementation is made in a timely manner
☐ The opinions expressed herein are based on my education, training, and experience
☐ The methodology employed is reliable and generally accepted in my field
☐ I have reliably applied the principles and methods to the facts of this case
☐ The opinions expressed are held to a reasonable degree of professional certainty

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XIV. Signature and Attestation

I declare under penalty of perjury that the foregoing is true and correct to the best of my knowledge, information, and belief.

Expert Signature: ___________________________________

Printed Name: [________________________________]

Date: [__/__/____]

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XV. Reservation of Rights

I reserve the right to further supplement this report should additional information become available, including but not limited to:
- Additional discovery
- Additional depositions
- Additional documents produced
- Additional testing or analysis

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XVI. Incorporation by Reference

Except as specifically modified herein, all opinions, conclusions, methodology, and other content of my original report dated [__/__/____] and any prior supplemental reports remain in full force and effect.

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Sources and References

• Federal Rules of Civil Procedure, Rule 26(e) - https://www.law.cornell.edu/rules/frcp/rule_26
• Federal Rules of Civil Procedure, Rule 26(a)(2)(B) - https://www.law.cornell.edu/rules/frcp/rule_26
• Federal Rules of Evidence, Rule 702 - https://www.law.cornell.edu/rules/fre/rule_702

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IMPORTANT TIMING NOTES:

Under FRCP 26(e)(2), supplementation must be made by the time the party's pretrial disclosures under Rule 26(a)(3) are due. Supplementations should be made at appropriate intervals during the discovery period and with special promptness as the trial date approaches. Failure to timely supplement may result in exclusion of testimony under FRCP 37(c)(1).