Metadata is loosely defined as "data about data." More specifically, the term refers to the embedded stratum of data in electronics file that may include such information as who authored a document, when it was created, what software was used, any comments embedded within the content, and even a record of changes made to the document.
A number of jurisdictions have issued opinions on the duties of an attorney who receives documents with metadata. The Washington State Bar Association recently issued the most recent opinion on the subject. You can read the full text of the opinion, which is very short, here. Go here for a summary of the opinions on this subject from other jurisdictions. I also recently mentioned (here) an interesting article on the conflicting positions of the ABA and New York's Committee on Professional Responsibility on the possible ethical implications of searching for and examining metadata in digital documents that lawyers receive from other lawyers.While metadata is often harmless, it can potentially include sensitive, confidential, or privileged information. As such, it presents a serious concern for attorneys charged with maintaining confidentiality -- both their own and their clients. Professional responsibility committees at several bar associations around the country have weighed in on attorneys' ethical responsibilities regarding metadata, but there is no clear consensus on the major metadata issues. To help track current views on metadata and ethics, we've assembled the following chart.
According to the recent WSBA opinion, lawyers may review readily accessible metadata that an opposing counsel unwittingly transmits in an electronic document but must not use software to extract such metadata from a “scrubbed” document. It places the duty to prevent the disclosure of data on the sender and only imposes on the recipient a duty to notify the sender that the document contains readily accessible metadata. The recipient is not ethically obligated to stop reading the document or to return the document, but cannot attempt to dig up metadata that the sender affirmatively tried to remove. Such conduct would violate the rules regarding respect for third parties' rights and conduct prejudicial to justice.