When a lawyer receives a document or electronically stored information and knows or reasonably should know it was sent by mistake, the ethics rules for the receiving lawyer in an inadvertent disclosure start with one duty: promptly notify the sender. That is all ABA Model Rule 4.4(b) requires on its own. Whether you must also stop reading, return the material, or destroy copies depends on your state’s version of the rule, any court order in the case, and the federal discovery rules that take over once the producing party asserts privilege.1American Bar Association. Comment on Rule 4.4
What the Model Rule Requires
Model Rule 4.4(b) is narrower than most lawyers assume. A lawyer who receives a document relating to the representation and “knows or reasonably should know that the document was inadvertently sent shall promptly notify the sender.”1American Bar Association. Comment on Rule 4.4 Notification is the whole of the obligation.
The rule does not require returning the document, deleting it, or stopping your review. Comment 2 says so directly: “Whether the lawyer is required to take additional steps, such as returning the document or electronically stored information, is a matter of law beyond the scope of these Rules.”1American Bar Association. Comment on Rule 4.4 Comment 3 calls the choice to voluntarily return a document unread “a matter of professional judgment ordinarily reserved to the lawyer.” ABA Formal Opinion 05-437 confirmed this in 2005.2American Bar Association. Formal Ethics Opinion 05-437
Once you notify, the ball is in the sender’s court. They can assert privilege, seek a protective order, or invoke the clawback procedure. Under the Model Rule, your ethical duty ends with the call or letter.
When the Duty Is Triggered
The “knows or reasonably should know” standard is objective. You cannot avoid the obligation by claiming you did not look closely enough to realize what you were holding. If a competent attorney in your position would have recognized the mistake, the duty attaches.
That standard matters most in large productions, where a reasonable attorney paging through a batch of documents will often spot an obvious privilege indicator: an email to outside counsel marked privileged, a memo captioned “Attorney-Client Communication,” a draft prepared in anticipation of litigation. The moment that recognition is reasonable, the clock starts on prompt notification.
States That Require More Than Notification
Plenty of states reject the ABA’s notification-only approach. Some jurisdictions require the receiving lawyer to take three steps: stop reading the document immediately, notify the sender, and follow the sender’s instructions about return or destruction.3American Bar Association. Ethics Corner: Inadvertent Disclosure — Traps Await the Unwary Others require some additional steps short of the full three-part protocol. A few states have no analog to Rule 4.4(b) at all, leaving receiving lawyers under only the general duty of good faith and whatever procedural rules apply.
The variation is not academic. If your state mandates ceasing review and you keep reading a plainly privileged settlement memo to mine opposing strategy, you are exposed to discipline no matter what the ABA Model Rule says. Lawyers admitted in multiple jurisdictions, or handling cases that touch several states, need to confirm which rule applies before relying on the Model Rule’s more permissive baseline.
What to Do When a Clawback Notice Arrives
Notification is one track. The federal civil rules are another, and they take over once the producing party asserts privilege over the material you received. Under Federal Rule of Civil Procedure 26(b)(5)(B), a clawback notice triggers specific obligations for the receiving party. You must promptly return, sequester, or destroy the identified material and any copies. You cannot use or disclose the information until the privilege claim is resolved. If you already shared the document with someone else before the notice arrived, you must take reasonable steps to retrieve it.4Legal Information Institute. Federal Rules of Civil Procedure Rule 26
Sequestration is the middle path when you believe the document is not actually privileged. Rather than destroying material that may turn out to be fair game, you lock it down where your litigation team cannot access it and present it to the court under seal for a ruling. The producing party must preserve the information until the dispute is resolved.
Rule 4.4(b) and Rule 26(b)(5)(B) are separate obligations running on different tracks. Complying with one does not satisfy the other. Notification is an ethics duty owed from the moment you reasonably should recognize the mistake; the clawback duties are procedural, triggered only when the sender formally asserts privilege.
Metadata Counts as Inadvertent Disclosure
Electronic documents carry embedded data the sender may not realize is there. Track changes, internal comments, revision history, author names, and editing timestamps all live beneath the surface of a Word file or spreadsheet. Produced in native format, that metadata travels with the document and can reveal privileged strategy notes or confidential client communications.
The ABA’s position, set out in Formal Opinion 06-442, is that the Model Rules contain no specific prohibition against reviewing metadata in documents you receive. The duty triggered by metadata is the same one that applies to any inadvertent disclosure: if you know or reasonably should know the metadata was sent inadvertently, you must notify the sender under Rule 4.4(b).1American Bar Association. Comment on Rule 4.4 Comment 2 to the rule includes “embedded data (commonly referred to as ‘metadata’)” within its scope on the same inadvertence condition.
State rules diverge here as well. Jurisdictions that prohibit reviewing inadvertently disclosed privileged documents tend to extend that prohibition to metadata containing protected information. More permissive jurisdictions generally allow metadata review on the same terms as any other received document.
What Happens If You Get It Wrong
The most serious consequence for a receiving lawyer who mishandles an inadvertent disclosure is disqualification. There is no single uniform test, but the analysis typically turns on whether the receiving lawyer complied with their ethical obligations by notifying the sender and ceasing review, whether the producing party took reasonable steps to protect the privilege, and whether allowing the lawyer to stay in the case would create prejudice that undermines the fairness of the proceeding.
The cases where disqualification actually happens involve egregious facts. A lawyer who recognizes a document as privileged, continues reading, uses it in depositions or motion practice, and never notifies the sender is the classic candidate. In one California appellate decision, a court affirmed disqualification of both the lawyer and the entire firm after finding repeated, extensive efforts to exploit an inadvertently produced document during discovery.
Beyond disqualification, Federal Rule of Civil Procedure 37 gives courts a range of sanctions for noncompliance with discovery obligations. There are no fixed amounts. A court may order the noncompliant party or attorney to pay the opposing side’s reasonable expenses, including attorney’s fees, incurred in bringing the issue to the court’s attention.5Legal Information Institute. Federal Rules of Civil Procedure Rule 37 In complex commercial litigation, those fees alone can run to tens of thousands of dollars.
The remedial options go further. A judge can deem certain facts established against the noncompliant party, prohibit that party from supporting or opposing specific claims, strike pleadings, stay the proceedings, enter default judgment, or treat the violation as contempt.5Legal Information Institute. Federal Rules of Civil Procedure Rule 37 The safe harbor applies only when the failure was “substantially justified” or when circumstances would make sanctions unjust, and concealing a known inadvertent disclosure rarely qualifies.
Whatever tactical advantage a privileged document might offer, it is almost never worth being removed from the case, having your conduct examined in a published opinion, or drawing a bar complaint. Stop reading the moment privilege becomes apparent, notify the sender immediately, and sequester the material until the dispute is resolved.