Taking and Defending an Expert Deposition: A Practical Guide

Summary. This guide walks lawyers, and the clients who pay for expert discovery, through an expert deposition from the day reports are exchanged to the Daubert hearing, in the order the work actually happens. The first part covers the taking side: deciding whether and how long to depose, getting the expert's file by Rule 34 request and Rule 45 subpoena, noticing the deposition and settling the Rule 26(b)(4)(E) fee, researching the expert, building a modular outline, conducting the examination, and turning the transcript into a Rule 37(c)(1) or Rule 702 motion. The second part covers the defending side: structuring the engagement so consultants and testifiers stay separate, responding to the notice and subpoena, preparing the expert on the three Rule 26(b)(4)(C) exceptions, defending with proper objections and instructions, and handling errata, supplementation, and a continued deposition. Along the way it addresses remote and foreign depositions, fee disputes, budgets, and the cases courts cite at each decision point. A day-by-day worked example follows a patent case's expert calendar from rebuttal reports to the Daubert filing, and the guide closes with common mistakes, an FAQ, and practical takeaways.

The rebuttal reports arrive on a Friday afternoon. The scheduling order gives you 24 days to depose the other side's three experts, defend your own two, and then 14 more days to file Daubert motions. Nobody has subpoenaed anyone's file, nobody has agreed on fees, and one of your experts just mentioned that she "spoke with a couple of the client's engineers" while writing her report.

That is the normal state of expert discovery, and it is why expert depositions are won or lost on logistics before anyone is sworn. This guide is the procedural companion to Expert Depositions: Taking Apart the Opinion, Protecting Your Own Expert, and Building the Daubert Record, which explains the doctrine. Here the focus is what to do, in what order, and what it costs.

The short answer

For the taking side, the sequence is: decide whether a full or a short deposition serves the case; get the expert's working file well before the deposition through a Fed. R. Civ. P. 34 request to the party and a Fed. R. Civ. P. 45 subpoena served with the notice; agree on the expert's fee in writing, because you will pay it under Fed. R. Civ. P. 26(b)(4)(E); build a modular outline organized around the elements of Fed. R. Evid. 702; lock the opinions and close the doors at the start and the end; and turn the transcript into a motion within days, while it is fresh.

For the defending side, the sequence is: keep consulting and testifying roles in different people; make the report's lists of materials considered and assumptions supplied by counsel complete; produce the file on time; prepare the expert in sessions as long as the deposition, on the report, the opposing report, prior testimony, and the three categories of attorney communications that are discoverable; object to form and instruct only on privilege, a court order, or a Fed. R. Civ. P. 30(d)(3) motion; and fix any substantive error through a Rule 26(e) supplement rather than a contradictory errata sheet.

The legal framework in one table

Wright & Miller cover expert discovery at 8A Federal Practice and Procedure §§ 2029 through 2034 (3d ed.), with the 1993 report requirement at § 2031.1, the 2010 amendments at § 2031.2, consulting experts at § 2032, and fees at § 2034. The Advisory Committee notes to the 1993 and 2010 amendments to Rule 26 and the 2023 amendment to Rule 702 are the best short explanations of why the rules read as they do.

The cases you will cite, and when

Most expert-deposition disputes recur, and so do the authorities. Keep this table next to the outline.

Timeline at a glance

Expert schedules vary, but the shape is constant. Count from the day the report you will depose on is served.

Part One: Taking the expert deposition

Step 1: Decide whether to take a full deposition, a short one, or none

Start with the purpose. A deposition can lay the foundation for a Rule 702 motion, gather admissions for summary judgment, limit the expert to the report for Rule 37(c)(1) purposes, authenticate impeachment material, and give you a preview of the trial witness. It can also educate the expert about your attack and invite a supplemental report. Weigh four questions:

1. Is a Rule 702 motion realistic? If the report has a visible gap (an untested hypothesis, an unexplained rate, an assumption with no record support), the deposition is where the motion is built, and a full deposition is worth the cost.
2. Who decides the facts? A judge with a technical advisor rewards precise technical admissions; a jury rewards credibility and clean impeachment. Plan the questions for the audience who will eventually see them.
3. How experienced is the witness? A veteran who has testified fifty times will not be shaken on qualifications; spend the time on assumptions and application. A first-time expert is more likely to concede a methodological point.
4. What will it cost, and what is the case worth? A full day with a damages expert, counting your preparation and the fee you pay under Rule 26(b)(4)(E), can easily run into five figures.

The short alternative, sometimes called the summary approach, covers retention, compensation, materials, the complete list of opinions, and a final lock, and leaves the attack for trial. It is defensible when the report is defective on its face or when the case is unlikely to reach trial, but it leaves you without a preview of how the expert handles pressure. Skipping the deposition entirely is rarely wise; an expert who has not been locked in can stretch the report at trial, and policing that in real time is hard.

Sequence matters as well. The party with the burden on an issue usually presents its expert first, and rebuttal experts are deposed after the rebuttal report. When several reports come from one expert, negotiate time per report in the scheduling order under Fed. R. Civ. P. 16 rather than relying on the seven-hour default. If a single admission could end the case (a missing claim limitation, an untested causation theory), consider asking for an early expert deposition tied to a summary judgment schedule.

Step 2: Get the expert's file before you notice the deposition

The report lists what the expert considered; it usually does not attach the working files, and the First Circuit has held it need not. Get them three ways:

• A Rule 34 request to the party, ideally served early in discovery, defining "expert materials" to include everything a testifying expert considered and the expert's non-privileged communications.
• A Rule 45 subpoena rider served with the deposition notice, with a production date seven to ten days before the deposition. Some courts quash stand-alone document subpoenas to the other side's retained experts as an end run around Rule 26(b)(4), as in Marsh v. Jackson, 141 F.R.D. 431 (W.D. Va. 1992), so pairing the subpoena with the notice is the safer practice. Serve it on all parties as Rule 45(a)(4) requires.
• An expert stipulation that fixes what each side produces and when, and what neither side will seek (typically drafts, notes, and attorney communications beyond the Rule 26(b)(4)(C) exceptions).

What to ask for:

1. The engagement letter, invoices, and time entries (compensation is an exception to the protection).
2. Every document, data set, model, spreadsheet, script, and code repository the expert considered, in native format with formulas intact.
3. Notes of testing, inspections, interviews, and site visits, and the test protocols and raw results.
4. Communications with anyone other than the retaining lawyers: the client's employees, other experts, the expert's own staff.
5. Any written statement of assumptions provided by counsel.
6. A list of testimony beyond the four-year window, and transcripts of prior testimony on the same subject.
7. Prior reports on the same subject, publications, and teaching materials.

Do not ask for drafts or for counsel's comments on them; it signals unfamiliarity with Rule 26(b)(4)(B) and invites a motion you will lose. If the other side asserts that all expert materials are work product, cite the Ecuador cases and move to compel under Rule 37(a). If you need to show the expert the other side's confidential documents, or the other side's expert needs yours, check the protective order's disclosure-and-objection procedure for experts well in advance; see Negotiating a Protective Order and Filing Under Seal.

Step 3: Notice the deposition and settle the fee

A notice under Rule 30(b)(1) to the party that retained the expert is the ordinary way to schedule a retained expert's deposition; the party produces its witness. State the date, time, place, and method of recording under Rule 30(b)(3), and say whether it will be videotaped. If anyone will appear remotely, get a stipulation or order under Rule 30(b)(4). A non-retained expert who is not a party or a party's employee (a treating physician, a former employee) needs a Rule 45 subpoena with the witness fee and mileage of 28 U.S.C. § 1821 tendered at service, and such witnesses often ask for a professional fee as well, which you should negotiate or bring to the court.

Then settle the retained expert's fee in writing: hourly rate for testimony; whether and how much preparation time you will pay for; travel time and expenses; time spent reviewing the transcript and errata; cancellation terms; and when the invoice is due. If you cannot agree, the court will set a reasonable fee under Rule 26(b)(4)(E), considering the expert's field and credentials, prevailing rates, the complexity of the subject, and what the expert charges the side that hired her. Many disputes evaporate if the deposing party offers to pay testimony time at the full rate and preparation time up to a cap, such as one hour of preparation per hour of testimony.

Step 4: Research the expert

Assemble everything the expert has said in public or under oath on the subject:

• Prior testimony. Work from the Rule 26(a)(2)(B)(v) list, then search dockets for cases outside the four-year window and for Daubert rulings involving the expert. Ask lawyers who have deposed her before for transcripts, and check whether a protective order in the earlier case restricts their use.
• Publications and teaching. Articles, books, slide decks, course materials, patents, and conference talks. Look for statements of method, error rates, and standards that the report departs from.
• Credentials. Verify degrees, licenses, certifications, and employment. Overstated credentials are rare and devastating.
• Online presence. Blog posts, social media, and company websites. Capture and preserve what you find before it changes.
• Retention patterns. How often the expert works for this firm, this client, or one side of the "v." Bias discovery is legitimate within limits; Behler v. Hanlon, 199 F.R.D. 553 (D. Md. 2001) allowed discovery of the percentage of income earned from expert work and the pattern of retention, while rejecting tax returns as overkill.

Step 5: Work with your own expert

Your expert is the best reader of the other expert's report. Ask for a short memo identifying the weakest steps in the analysis, the published standards the report ignores, the data the expert did not use, and the questions a peer reviewer would ask. Decide whether your expert should attend the deposition (the protective order must allow it) or be available by phone during breaks. If your testifying expert helps prepare the outline, remember that while counsel's communications with her are protected by Rule 26(b)(4)(C), her participation may be explored at her own deposition; some lawyers use a non-testifying consultant for this work, whose input is protected by Rule 26(b)(4)(D).

Step 6: Build the outline

Build in modules, not as a script. Each module states its goal, the documents you will use, the admissions you need, and the closing lock question. A time budget for a seven-hour day might look like this:

Prepare the exhibits: the report as the first exhibit, the CV, the invoices, the considered-materials list, the key documents, and every impeachment item, with enough copies (or a working exhibit-sharing platform) for everyone. Keep exhibit numbers consistent across depositions where the case uses sequential numbering. For general outlining technique, see the Preparing to Take a Deposition Checklist and the Deposition Practice Toolkit; the expert-specific templates are in the Expert Deposition Toolkit.

Step 7: Take the deposition

Open cleanly. State any stipulations on the record in full rather than agreeing to the "usual stipulations." Ask whether the expert brought documents and, if so, ask that they be produced. Ask what the expert reviewed to prepare; writings used to refresh recollection can be ordered produced under Rule 612. Ask whether the expert has formed any new opinions or done any new work since signing the report.

Run the funnels. For each opinion, start open ("Walk me through how you reached the 7 percent rate"), narrow with follow-ups, and close with short leading questions and the catch-all: "Is there anything else you relied on for that rate?"

Manage the witness, not the argument. If the defending lawyer makes a valid form objection, rephrase; if not, ask the witness to answer. If the expert lectures, repeat the question verbatim and say "move to strike as nonresponsive"; under Fed. R. Civ. P. 32(d)(3)(B), objections to the form of an answer are waived if not made at the deposition. If the expert asks you to define every term, adopt the report's own definitions or the court's claim construction. If she says she would have to look, hand her the document and wait.

Handle instructions not to answer. Put the question and the stated basis on the record, ask whether the witness will follow the instruction, and move on. Afterward, meet and confer, then move to compel under Rule 37(a)(3)(B)(i). Instructions on grounds other than privilege, a court order, or a Rule 30(d)(3) motion are improper, and courts can sanction them under Rule 30(d)(2).

Track the clock. Log time consumed by long nonresponsive answers and by breaks. If you need more time because the witness impeded the examination, Rule 30(d)(1) requires the court to allow it, but only a contemporaneous record will persuade the court.

Close the doors and keep it open if needed. Repeat the lock at the end: all opinions stated, nothing else relied on, no further work planned. If documents were withheld or produced late, say on the record that you are holding the deposition open for questioning on them.

Step 8: After the deposition: digest, motion, follow-up

Digest the transcript within a few days, organized by Rule 702 element and by opinion, with page and line citations for every concession. Draft the motion sections while the testimony is fresh. Calendar the errata deadline (30 days after the reporter's notice, if review was requested) and be ready to challenge contradictory changes. If the other side serves a "supplemental" report, decide whether to move to strike it under Rule 37(c)(1) as untimely new opinion, seek a continued deposition at the proponent's expense, or both. If summary judgment is coming, map each concession to the element it defeats; the expert's own testimony is the most persuasive evidence that no genuine dispute exists. Designations for trial follow later; see Designating and Playing Deposition Testimony at Trial.

Part Two: Defending the expert deposition

Step 1: Structure the engagement for discovery from the first day

Most expert-deposition disasters are built at retention, months before the deposition. Five structural choices prevent them:

1. Separate the consultant from the testifier. Facts known and opinions held by a consulting expert are protected under Rule 26(b)(4)(D) unless exceptional circumstances exist. That protection largely disappears for anything bearing on the testimony once the consultant is designated, as in Yeda Research & Development Co. v. Abbott GmbH & Co. KG, 292 F.R.D. 97 (D.D.C. 2013). Use different people, or decide at the outset that the consultant's file will be produced.
2. Retain through counsel, with a letter that defines the role. The engagement letter is discoverable as compensation material, so write it as if the other side will read it aloud: assignment, rates, billing practices, and confidentiality obligations, without editorial commentary about the case.
3. Keep the file, all of it. Materials the expert considered must be retained and disclosed even if she did not rely on them; a document-retention policy is no defense, as the Seventh Circuit held in Fidelity National Title Insurance Co. v. Intercounty National Title Insurance Co., 412 F.3d 745 (7th Cir. 2005). Send a written preservation instruction.
4. Route fact-gathering through counsel or document it. Communications with the client's engineers, accountants, or executives are not protected by Rule 26(b)(4)(C), which covers only the party's attorneys, so they will be explored. Have counsel present, or have the expert record what she asked and learned, and list those interviews as facts considered.
5. Make the report's two lists complete. The considered-materials list and the assumptions section are the two parts of the report most likely to produce a damaging exchange. Each assumption should be stated, attributed to counsel where counsel supplied it, and paired with the expert's reason for treating it as reasonable.

Invoices deserve a separate word. Because compensation is outside the protection, time entries such as "call with counsel re: weaknesses in the damages theory" will be read into the record. Ask the expert to keep entries neutral and factual ("call with counsel; reviewed sales data").

Step 2: Respond to the notice and the subpoena

When the notice arrives, confirm the date, the location or remote platform, the recording method, and the fee terms in writing. Written objections to a Rule 45 document subpoena must be served before the earlier of the compliance date or 14 days after service, under Rule 45(d)(2)(B); serve them on time even if you expect to produce most of what is requested. Typical objections target drafts and attorney communications (protected by Rule 26(b)(4)(B) and (C)), materials beyond the scope of the expert's assignment, and confidential third-party materials that the protective order requires to be handled differently. Decide early whether protected drafts and communications need to be logged; many expert stipulations say they need not be, and settling that point avoids a log of every email between counsel and the expert. For logging mechanics, see Preparing a Privilege Log; for subpoena responses generally, see the Rule 45 Subpoena Response Checklist.

Produce the considered materials completely and early. A late production invites a continued deposition at your expense, and an incomplete one invites a Rule 37(c)(1) motion. If you need a protective order to limit the deposition, move before the deposition date; Rule 26(c) relief obtained afterward rarely helps.

Step 3: Prepare the expert

Schedule preparation close to the deposition, and make at least one session as long as the deposition itself, so the expert experiences fatigue in practice rather than on the record. Assemble a binder (or a folder) with the report and exhibits, the considered materials, the opposing reports, the key documents in the case, the expert's prior testimony and publications on the subject, the CV, the engagement letter, and the invoices. Then cover these subjects:

• Mechanics. Who will attend, how long it will last, whether it is videotaped, how breaks work, and that no break may be taken while a question is pending except to discuss whether a privilege applies. If the deposition is remote, test the platform and set the room: alone, no messaging applications, only permitted materials.
• The deposing lawyer's goals. Locking opinions, closing doors, finding assumptions, testing the method, and collecting bias material. An expert who understands why a question is asked is less likely to volunteer.
• The three exceptions. Compensation; facts or data counsel provided that she considered; assumptions counsel provided that she relied on. Everything else about her communications with counsel is protected, and you will instruct her not to answer questions about drafts and counsel's comments.
• The report as script. For each opinion: the page, the one-sentence statement, the method in three sentences, and the key support. Questions outside the report get a truthful scope answer, not a new opinion.
• Hypotheticals, lists, and absolutes. Listen for changed facts inside a hypothetical, for questions asking for a complete list, and for "always" and "never." The honest answer to many of them is "I would need to analyze that, and I have not."
• Prior statements. Walk through every publication and prior report the other side may use, and prepare a candid explanation of any apparent inconsistency.
• Demeanor. Short, accurate answers; no sparring; no lecturing; a willingness to concede the obvious. Juries and judges trust experts who concede what should be conceded.

Two limits apply throughout. The opinions must be the expert's own, and ABA Model Rule of Professional Conduct 3.4(b) forbids counseling or assisting a witness to testify falsely. And anything the expert reviews to refresh recollection can be ordered produced under Fed. R. Evid. 612, so do not put privileged material in the preparation binder. Tell the expert to bring nothing to the deposition; whatever she brings, the other side may ask to see.

Step 4: Defend at the deposition

• Before the record opens, confirm the stipulations, the exhibit procedure, and, for remote depositions, the witness's setup.
• Object to form, briefly. "Objection, form," with a one-word basis if asked (compound, mischaracterizes the testimony, assumes facts not in evidence, incomplete hypothetical). Form objections not made at the deposition are waived, but speaking objections violate Rule 30(c)(2) and can draw sanctions under Rule 30(d)(2).
• Instruct not to answer only on the three permitted grounds: to preserve a privilege or work product protection (for example, a question about counsel's comments on a draft), to enforce a court-ordered limitation, or to present a Rule 30(d)(3) motion. If you invoke Rule 30(d)(3), suspend the deposition and file the motion promptly; Redwood v. Dobson, 476 F.3d 462 (7th Cir. 2007) shows what happens otherwise.
• Know your court's rule on conferring during breaks. Some courts follow Hall v. Clifton Precision, 150 F.R.D. 525 (E.D. Pa. 1993) and allow questioning about break-time conferences; others treat them as privileged. Act accordingly.
• Decide on redirect. Ask questions only to correct a genuine error or an answer produced by a misleading question, and only if you know the answer. A Daubert motion may be decided on the papers, so an uncorrected misstatement can matter more than it would with a fact witness.
• Request review on the record under Rule 30(e), so the 30-day errata window is available.

Step 5: Errata, supplementation, and the continued deposition

Review the transcript with the expert as soon as it arrives. Transcription errors and plain misstatements (a wrong date, a transposed number) go on the errata sheet with a reason for each change. Substantive changes are risky: the Seventh Circuit bars changes that contradict the transcript unless they are plausibly transcription errors, Thorn v. Sundstrand Aerospace Corp., 207 F.3d 383 (7th Cir. 2000), the Ninth allows corrective but not contradictory changes, Hambleton Bros. Lumber Co. v. Balkin Enterprises, Inc., 397 F.3d 1217 (9th Cir. 2005), the Tenth treats contradictory errata like sham affidavits, Garcia v. Pueblo Country Club, 299 F.3d 1233 (10th Cir. 2002), and the Third requires reasons and decides case by case, EBC, Inc. v. Clark Building Systems, Inc., 618 F.3d 253 (3d Cir. 2010). If the expert genuinely got something wrong, the usual route is a Rule 26(e) supplement that explains the correction, served promptly and before the Rule 26(a)(3) deadline, with an offer to make the expert available for a short continued deposition. Keep the supplement to correction; courts reject supplements that add new analysis or stronger opinions, as in Akeva L.L.C. v. Mizuno Corp., 212 F.R.D. 306 (M.D.N.C. 2002). For the errata mechanics in depth, see the Deposition Designation and Errata Checklist.

Step 6: Get ready for the Daubert hearing

Read the transcript as the judge will, marking every question the expert could not answer cleanly. Then choose among three responses: a declaration that explains, consistently with the testimony, the method or data the transcript left unclear; live testimony at a Rule 104(a) hearing; or narrowing the opinions you will offer. A declaration that contradicts the deposition without explanation invites the sham-affidavit rule associated with Cleveland v. Policy Management Systems Corp., 526 U.S. 795 (1999). Withdrawing one weak opinion often protects the strong ones. And remember the end state: if the testimony is excluded on appeal and the remaining evidence is insufficient, the court of appeals may direct judgment rather than order a new trial, Weisgram v. Marley Co., 528 U.S. 440 (2000), which is exactly what happened in Sardis v. Overhead Door Corp., 10 F.4th 268 (4th Cir. 2021).

Remote, foreign, and multi-expert logistics

Remote depositions. Get the stipulation or order under Rule 30(b)(4), name the platform, and specify the exhibit procedure (pre-marked exhibits delivered sealed, or shared on a platform that records what the witness sees). Require the witness to be alone, with no messaging applications and only listed materials, and frame the camera to show the witness's hands and desk. Arrange a backup audio line and confirm that the court reporter can swear the witness remotely under the law of the place where the witness sits; Fed. R. Civ. P. 28 governs who may administer the oath.

Experts abroad. A party's own expert who lives abroad is usually produced voluntarily, and the scheduling order can require it. Otherwise, Rule 28(b) permits depositions in a foreign country under a treaty or convention, by letter of request transmitted under 28 U.S.C. § 1781, on notice, or by commission. The Hague Evidence Convention is available but not mandatory for discovery from parties, Societe Nationale Industrielle Aerospatiale v. United States District Court, 482 U.S. 522 (1987). Several countries restrict depositions on their soil even of willing witnesses; check the State Department's judicial assistance information for the country before you book travel. If the deposition is for use in a foreign proceeding instead, the route is 28 U.S.C. § 1782; see Seeking or Opposing Section 1782 Discovery.

Several experts, short window. Stagger depositions so the same lawyer is not defending one expert and taking another on consecutive days, put the burden-holder's experts first, and agree in advance on time per report. If one expert covers several patents or both liability and damages, negotiate additional hours rather than fighting about them at the end of the day.

Where courts differ, and how to plan for it

Check local law on each of these before the deposition, not during it.

Costs, fees, and budgets

Retained technical and economic experts commonly bill several hundred to more than a thousand dollars an hour. For a client, the realistic budget for one contested expert deposition, counting attorney preparation on both sides, the expert's preparation and testimony, and the transcript and video, often lands in the tens of thousands of dollars. Clients should hear that number before the retention letter is signed, and should also hear the other half of the calculation: a deposition that produces a successful Rule 702 motion can remove the largest number in the case.

Common mistakes, and how to avoid them

• Reading the expert's spreadsheets for the first time at the table. Get native files a week ahead and have your own expert open them.
• Fighting about drafts. They are protected. Spend the time on the three exceptions.
• No fee agreement. The dispute arrives with the invoice, after the testimony, when you have no leverage.
• Outlines that follow the report page by page. Organize by opinion and by Rule 702 element, so the transcript maps onto the motion.
• Forgetting the lock at the end. The opening lock is undermined by everything the expert said in between; repeat it.
• Defending without a structural plan. A consultant turned testifier, missing notes, and editorial invoices are problems you cannot fix at the deposition.
• Instructing not to answer on relevance or scope. Neither is a permitted ground under Rule 30(c)(2).
• Repairing testimony with errata. Contradictory changes are struck in several circuits and look worse than the original answer.
• Waiting to digest the transcript. The Daubert deadline is usually two to four weeks after expert discovery closes.

Worked example: a 24-day expert calendar in a patent case

Kestrel Networks has sued Brightwave Semiconductor for infringing a Wi-Fi patent. You represent Brightwave. Opening reports came in last month; rebuttal reports were served on a Friday, Day 0. Expert discovery closes on Day 24, and Rule 702 motions are due on Day 38. You will take the depositions of Kestrel's technical expert and its damages expert, Dr. Whitlock, and defend Brightwave's damages expert, Mr. Osei, and its noninfringement expert.

The pattern to notice is that every decisive event happened before or after the deposition days themselves: the subpoena rider, the fee agreement, your expert's memo, the invoice review, and the errata fight. The depositions mostly confirmed what the preparation had found. For the substantive damages questions behind this example, see Proving and Attacking Patent Damages and the Patent Damages Checklist; for a damages expert in a misappropriation case, see Proving or Defending Against Trade Secret Damages.

Frequently asked questions

How much notice do I need to give for an expert deposition? Rule 30(b)(1) requires "reasonable written notice." In practice, notice the deposition the day the report is served, and give at least 14 days where possible; under Rule 32(a)(5)(A), a deposition generally cannot be used against a party who received less than 14 days' notice and promptly moved for a protective order.

Do I have to pay for the other side's expert to prepare? It depends on the court and on what you agree. Rule 26(b)(4)(E) requires a reasonable fee for time spent responding to discovery, and courts disagree about whether that includes preparation. Settle it before the deposition with a cap.

Can I bring my own expert to the deposition? Usually, if the protective order allows the expert access to the confidential information that will be discussed. Witness sequestration under Fed. R. Evid. 615 does not by itself apply to depositions; the court can limit who attends under Rule 26(c)(1)(E).

The expert brought notes to the deposition. What now? Ask to see them and mark them as an exhibit. Materials the expert uses at the deposition, and writings used to refresh recollection, are generally discoverable, and a refusal belongs on the record for a motion to compel.

Can I use the expert's deposition at trial if she is available to testify? For impeachment, yes, under Rule 32(a)(2). As substantive evidence, only if the witness is unavailable under Rule 32(a)(4) (including being more than 100 miles from the courthouse), if the court allows it in exceptional circumstances, or if the parties agree. Plan as though your expert's deposition may be played.

The other side served a "supplemental" report after the deposition. What are my options? Move to strike under Rule 37(c)(1) if it adds new opinions or new analysis rather than correcting an error, ask for a continued deposition at the proponent's expense, or both. Courts limit supplementation to correcting inaccuracies and filling gaps with information that was not available earlier, as in Keener v. United States, 181 F.R.D. 639 (D. Mont. 1998).

Should my expert read the opposing expert's deposition before her own? Usually yes, because it shows her the issues and the questioning style. Remember that what she reviews may be considered material and may be discoverable, which is rarely a problem when the document is the other side's own transcript.

Practical takeaways

• Expert depositions are won in the two weeks before them: the file, the fee, the research, and your own expert's memo.
• Pair every deposition notice with a subpoena rider and a production date a week ahead.
• Organize the outline by opinion and by Rule 702 element, with a time budget, and lock the opinions at both ends.
• On defense, fix structure early: separate consultants, preserve the file, neutral invoices, complete lists of materials and assumptions.
• Object to form, instruct only on the three permitted grounds, and request Rule 30(e) review on the record.
• Correct substance through disclosed supplementation, not contradictory errata.
• Digest the transcript by element within days; the motion deadline is closer than it looks.

This document is general information, not legal advice for any particular situation; the law changes, and the facts matter.

Related Documents

Related Articles

• Expert Depositions: Taking Apart the Opinion, Protecting Your Own Expert, and Building the Daubert Record: the doctrine behind every step in this guide.
• Expert Witnesses After the 2023 Amendment to Rule 702: the admissibility standard the deposition serves.
• Using Depositions at Trial and on Summary Judgment: Rule 32, designations, errata, and impeachment.
• The Art of Defending Depositions in Federal Court: the general defending playbook.

Related Guides

• Designating and Playing Deposition Testimony at Trial: what happens to the transcript at trial.
• Litigating Substantial Similarity in a Copyright Case: where software and music experts fit in a copyright case.
• Proving or Defending Against Trade Secret Damages: damages experts in misappropriation cases.
• Negotiating a Protective Order and Filing Under Seal: expert access to confidential information.
• Seeking or Opposing Section 1782 Discovery: expert discovery for use abroad.

Related Checklists

• Expert Deposition Preparation Checklist: the task list version of this guide.
• Defending a Deposition Checklist: general defending tasks.
• Deposition Designation and Errata Checklist: errata and designations step by step.
• Rule 45 Subpoena Response Checklist: responding to a subpoena for the expert's file.
• Summary Judgment Motion Checklist: using expert concessions in a Rule 56 motion.

Related Toolkits

• Expert Deposition Toolkit: outline frameworks, subpoena riders, and protection maps.
• Expert Witness Toolkit: selecting, retaining, and managing experts.
• Deposition Use Toolkit: designation charts and impeachment scripts.
• Nonparty Discovery Toolkit: subpoenas to non-retained experts and other nonparties.
• Litigation Sanctions and Professional Responsibility Toolkit: when deposition conduct turns into a sanctions motion.