Metadata — which is embedded “data about data” — may reveal information about an electronic document’s creation and modification, including who authored or commented upon a draft, when they did so, and most importantly what edits or other contributions were made. Placing a metadata “bug” in an e-mail enables the sender to determine the subsequent route of the e-mail, including the recipients’ comments. Many software programs that attorneys use to draft legal documents generate metadata.

As guidelines continue to evolve for the discovery of increasingly complex electronically stored information (ESI), the issue of whether metadata must be included in production of ESI has been litigated with some frequency. Further, debate has raged over the ethics of searching through the metadata of an opposing party’s electronic production.

To Produce or Not to Produce

Cases regarding metadata production have most often arisen in disputes over newly amended Federal Rule of Civil Procedure 34(b)’s requirements regarding acceptable formats of production. That rule requires ESI to be produced “in a form or forms in which it is ordinarily maintained or in a reasonably usable form.”

Several courts have tackled the question of whether ESI must be produced with metadata intact. In In Re Payment Card Interchange Fee & Merchant Discount Antitrust Litig., 2007 WL 121426 (E.D.N.Y. Jan. 12, 2007), plaintiffs stripped their text-searchable electronic documents of metadata. Defendants moved to compel plaintiffs to reproduce the documents with metadata. The court granted defendants’ motion prospectively only. The court reasoned that in stripping the metadata, plaintiffs had run afoul of the Advisory Committee’s statement that data ordinarily kept in electronically searchable form “should not be produced in a form that removes or significantly degrades this feature.” Id. at *4. The court held that requiring the plaintiffs to include metadata in future productions would not impose an undue burden. A retrospective ruling, however, would impose an undue burden on plaintiffs, who had produced documents without metadata for several months without receiving any objection from defendants.

Another court has articulated a stronger presumption regarding whether the producing party must include metadata in its production of ESI. In Williams v. Sprint/United Management Co., 230 F.R.D. 640 (D. Kan. 2005), the court held that the producing party should produce its ESI with metadata intact unless (i) the producing party timely objects to the production of metadata; (ii) the parties agree that metadata should not be produced; or (iii) the producing party requests a protective order. Id. at 652. The court reasoned that placing the burden on the producing party is reasonable because “metadata is an inherent part of an electronic document, and its removal ordinarily requires an affirmative act by the producing party that alters the electronic document.” Id. While the defendant claimed that the metadata was irrelevant, the court disagreed and further observed that, in any event, defendant had unilaterally scrubbed the metadata and failed to assert a relevancy objection.

Rejecting Williams as “not persuasive,” the court in Kentucky Speedway, LLC v. National Association of Stock Car Auto Racing, Inc., 2006 WL 5097354 (E.D. Ky. Dec. 18, 2006), held that “‘[e]merging standards of electronic discovery appear to articulate a general presumption against the production of metadata’” (citation omitted). Id. at *8. The court stated its presumption that “[i]n most cases and for most documents, metadata does not provide relevant information.” Id. The court further held that parties should address questions regarding the relevance of metadata in their Rule 26(f ) discovery conference. The court emphasized that the requesting party had not made any showing of a particularized need for the metadata.

Reviewing an Adversary’s Metadata: The Ethics Debate

To the extent that some courts have indicated a presumption in favor of requiring parties to produce metadata, their holdings beg further discussion of how a requesting party may use the metadata it receives and, in particular, concerns about privileged communications that could be contained therein. Case law on whether and under what circumstances metadata may be examined by an adversary is sparse, though the ethics committee of the ABA and a handful of states have issued opinions. Noting the need for clear ethical guidance about searching metadata, and responding to numerous questions from attorneys, a handful of state and ABA ethics committees have issued opinions on the propriety of reviewing an adversary’s metadata.

The ABA Standing Committee on Ethics and Professional Responsibility, in Formal Opinion 06-442 (Aug. 5, 2006), observed that the ABA Model Rules of Professional Conduct “do not contain any specific prohibition against a lawyer’s reviewing and using the embedded information in electronic documents.” The opinion noted, however, that Model Rule 4.4(b) requires a lawyer who receives information she knows or should know was sent inadvertently to “promptly notify the sender.” Most importantly, the opinion encouraged attorneys who send ESI to remove metadata from the ESI.

Like the ABA, the Maryland State Bar Association’s Committee on Ethics has opined that there is no ethical problem with searching metadata that a an opposing party has produced (Op. 2007-09, Oct. 19, 2006). Even more permissively, the Maryland committee stated that “there is no ethical violation if the recipient attorney . . . reviews or makes use of the metadata without first ascertaining whether the sender intended to include such metadata.” The Maryland committee also stated that lawyers who produce ESI must take reasonable measures to avoid disclosing privileged information.

Not all state committees agree with the ABA and Maryland approaches. The District of Columbia Legal Ethics Committee’s opinion prohibits a lawyer from reviewing an adversary’s metadata if the lawyer has “actual knowledge” that the adversary sent the metadata inadvertently. The D.C. committee explained that “actual knowledge” may exist (i) when a lawyer hears of the mistake before reviewing the document; (ii) when a lawyer notices immediately upon review that the adversary obviously sent the data inadvertently; or (iii) when a lawyer uses a system to search all incoming ESI in hopes of discovering privileged information (District Of Columbia Legal Ethics Committee Opinion 341, September 2007). Otherwise, the receiving lawyer may ethically review the metadata — mere uncertainty regarding whether the ESI is privileged “does not trigger an ethical obligation by the receiving lawyer to refrain from reviewing the metadata.” The opinion also emphasizes that outside the context of discovery or a subpoena (that is, in the context of voluntary disclosure), a lawyer is ethically obligated to avoid inadvertently disclosing privileged information, and must use reasonably available methods to remove privileged information from electronically transmitted documents.

In stark contrast to the ABA, ethics committees in New York and Alabama have opined that a lawyer may not search an adversary’s ESI to uncover confidential information. The New York State Bar Association Committee on Professional Ethics’ Opinion 749 (Dec. 14, 2001) prohibits a lawyer from mining metadata or “bugging” emails for metadata, on the grounds that doing so is an unacceptable violation of the adversary’s attorney-client relationship. Mining metadata, states the opinion, is “substantively analogous to less technologically sophisticated means of invading the attorney-client relationship.” The linchpin of the New York opinion is its presumption that when the adversary discloses ESI that contains metadata, although the adversary intends for opposing counsel to receive the “visible” document, absent an explicit direction to the contrary, the adversary did not intend for opposing counsel to receive “hidden” material or information about the authors of revisions to the document. And unlike the ABA opinion, which emphasizes that computer users can protect themselves by “scrubbing” some kinds of metadata or negotiating confidentiality agreements or protective orders, the New York opinion emphasizes that parties cannot always de-bug ESI they produce.

Like the New York committee, the Alabama State Bar’s ethics panel states that “[j]ust as a sending lawyer has an ethical obligation to reasonably protect the confidences of a client, the receiving lawyer also has an ethical obligation to refrain from mining an electronic document.” (Alabama State Bar Ethics Opinion RO-2007-02, Mar. 14, 2007). In addition, the Alabama opinion requires lawyers to use reasonable care to avoid disclosing privileged metadata. “Reasonable care” varies with the individual circumstances and includes considerations of such factors as (i) steps the lawyer takes to avoid disclosing metadata; (ii) the metadata’s nature and scope; (iii) the document’s subject matter; and (iv) the recipient’s identity. The Alabama opinion distinguishes between voluntary communication between opposing counsel and discovery when the metadata may be relevant to the litigation; in cases of the latter type, the opinion advises attorneys to seek the court’s instruction.

The Florida State Bar Association, too, has stated that a lawyer who sends ESI should take care to protect its confidentiality, and that a receiving lawyer should not mine metadata. (Florida State Bar Ethics Opinion 06-2, Sep. 15, 2006). The Florida opinion presumes that disclosure of metadata is usually inadvertent. The opinion does not, however, address metadata ESI produced during discovery.


It is critical for litigants to consider the implications of producing metadata embedded in electronic documents. When producing ESI, a party should use reasonably available methods to remove privileged metadata. Should a receiving party receive metadata in connection with ediscovery, that party should exercise care in handling it, in order to avoid ethical issues. Finally, to avoid future discovery disputes, parties are advised to discuss the production of metadata — including the ramifications of inadvertent production — at their Rule 26(f) conference. ¦