A retained expert's report must contain a complete statement of all opinions and the basis for each, the facts or data considered, any exhibits used to summarize or support the opinions, the expert's qualifications and publications, prior testimony over a defined period, and compensation.
Opinions not disclosed in the report are generally excluded at trial.
Alternative Names:
Rule 26(a)(2)(B) Report, Written Expert Report
Why it Matters?
The report defines the outer boundary of what the expert may say, which makes drafting scope a strategic decision rather than a formality. Opinions omitted are usually lost, while opinions stated too broadly invite Daubert challenge. The facts-or-data-considered requirement is also a discovery lever, since it reaches materials the expert reviewed even if not relied upon.
Frequently Confused with
Related terms
Frequently asked questions
Can an expert testify to opinions not in the report?
Are draft reports discoverable?


