The opinion of the court was delivered by: Shira A. Scheindlin, United States District Judge
The world was a far different place in 1849, when Henry David Thoreau opined (in an admittedly broader context) that "[t]he process of discovery is very simple."*fn1 That hopeful maxim has given way to rapid technological advances, requiring new solutions to old problems. The issue presented here is one such problem, recast in light of current technology: To what extent is inaccessible electronic data discoverable, and who should pay for its production?
The Supreme Court recently reiterated that our "simplified notice pleading standard relies on liberal discovery rules and summary judgment motions to define disputed facts and issues and to dispose of unmeritorious claims."*fn2 Thus, it is now beyond dispute that "[b]road discovery is a cornerstone of the litigation process contemplated by the Federal Rules of Civil Procedure."*fn3 The Rules contemplate a minimal burden to bringing a claim; that claim is then fleshed out through vigorous and expansive discovery.*fn4
In one context, however, the reliance on broad discovery has hit a roadblock. As individuals and corporations increasingly do business electronically*fn5 — using computers to create and store documents, make deals, and exchange e-mails — the universe of discoverable material has expanded exponentially.*fn6 The more information there is to discover, the more expensive it is to discover all the relevant information until, in the end, "discovery is not just about uncovering the truth, but also about how much of the truth the parties can afford to disinter."*fn7
This case provides a textbook example of the difficulty of balancing the competing needs of broad discovery and manageable costs. Laura Zubulake is suing UBS Warburg LLC, UBS Warburg, and UBS AG (collectively, "UBS" or the "Firm") under Federal, State and City law for gender discrimination and illegal retaliation. Zubulake's case is certainly not frivolous*fn8 and if she prevails, her damages may be substantial.*fn9 She contends that key evidence is located in various e-mails exchanged among UBS employees that now exist only on backup tapes and perhaps other archived media. According to UBS, restoring those e-mails would cost approximately $175,000.00, exclusive of attorney time in reviewing the e-mails.*fn10 Zubulake now moves for an order compelling UBS to produce those e-mails at its expense.*fn11
UBS hired Zubulake on August 23, 1999, as a director and senior salesperson on its U.S. Asian Equities Sales Desk (the "Desk"), where she reported to Dominic Vail, the Desk's manager. At the time she was hired, Zubulake was told that she would be considered for Vail's position if and when it became vacant.
In December 2000, Vail indeed left his position to move to the Firm's London office. But Zubulake was not considered for his position, and the Firm instead hired Matthew Chapin as director of the Desk. Zubulake alleges that from the outset Chapin treated her differently than the other members of the Desk, all of whom were male. In particular, Chapin "undermined Ms. Zubulake's ability to perform her job by, inter alia: (a) ridiculing and belittling her in front of co-workers; (b) excluding her from work-related outings with male co-workers and clients; (c) making sexist remarks in her presence; and (d) isolating her from the other senior salespersons on the Desk by seating her apart from them."*fn12 No such actions were taken against any of Zubulake's male co-workers.
Zubulake ultimately responded by filing a Charge of (gender) Discrimination with the EEOC on August 16, 2001. On October 9, 2001, Zubulake was fired with two weeks' notice. On February 15, 2002, Zubulake filed the instant action, suing for sex discrimination and retaliation under Title VII, the New York State Human Rights Law, and the Administrative Code of the City of New York. UBS timely answered on March 12, 2002, denying the allegations. UBS's argument is, in essence, that Chapin's conduct was not unlawfully discriminatory because he treated everyone equally badly. On the one hand, UBS points to evidence that Chapin's anti-social behavior was not limited to women: a former employee made allegations of national origin discrimination against Chapin, and a number of male employees on the Desk also complained about him. On the other hand, Chapin was responsible for hiring three new females employees to the Desk.*fn13
Discovery in this action commenced on or about June 3, 2002, when Zubulake served UBS with her first document request. At issue here is request number twenty-eight, for "[a]ll documents concerning any communication by or between UBS employees concerning Plaintiff."*fn14 The term document in Zubulake's request "includ[es], without limitation, electronic or computerized data compilations." On July 8, 2002, UBS responded by producing approximately 350 pages of documents, including approximately 100 pages of e-mails. UBS also objected to a substantial portion of Zubulake's requests.*fn15
On September 12, 2002 — after an exchange of angry letters*fn16 and a conference before United States Magistrate Judge Gabriel W. Gorenstein — the parties reached an agreement (the "9/12/02 Agreement"). With respect to document request twenty-eight, the parties reached the following agreement, in relevant part:
Defendants will  ask UBS about how to retrieve
e-mails that are saved in the firm's computer system
and will produce responsive e-mails if retrieval is
possible and Plaintiff names a few individuals.*fn17
Pursuant to the 9/12/02 Agreement, UBS agreed unconditionally to produce responsive e-mails from the accounts of five individuals named by Zubulake: Matthew Chapin, Rose Tong (a human relations representation who was assigned to handle issues concerning Zubulake), Vinay Datta (a co-worker on the Desk), Andrew Clarke (another co-worker on the Desk), and Jeremy Hardisty (Chapin's supervisor and the individual to whom Zubulake originally complained about Chapin). UBS was to produce such e-mails sent between August 1999 (when Zubulake was hired) and December 2001 (one month after her termination), to the extent possible.
UBS, however, produced no additional e-mails and insisted that its initial production (the 100 pages of e-mails) was complete. As UBS's opposition to the instant motion makes clear — although it remains unsaid — UBS never searched for responsive e-mails on any of its backup tapes. To the contrary, UBS informed Zubulake that the cost of producing e-mails on backup tapes would be prohibitive (estimated at the time at approximately $300,000.00).*fn18
Zubulake, believing that the 9/12/02 Agreement included production of e-mails from backup tapes, objected to UBS's non-production. In fact, Zubulake knew that there were additional responsive e-mails that UBS had failed to produce because she herself had produced approximately 450 pages of e-mail correspondence. Clearly, numerous responsive e-mails had been created and deleted*fn19 at UBS, and Zubulake wanted them.
On December 2, 2002, the parties again appeared before Judge Gorenstein, who ordered UBS to produce for deposition a person with knowledge of UBS's e-mail retention policies in an effort to determine whether the backup tapes contained the deleted e-mails and the burden of producing them. In response, UBS produced Christopher Behny, Manager of Global Messaging, who was deposed on January 14, 2003. Mr. Behny testified to UBS's e-mail backup protocol, and also to the cost of restoring the relevant data.
C. UBS's E-Mail Backup System
In the first instance, the parties agree that e-mail was an important means of communication at UBS during the relevant time period. Each salesperson, including the salespeople on the Desk, received approximately 200 e-mails each day.*fn20 Given this volume, and because Securities and Exchange Commission regulations require it,*fn21 UBS implemented extensive e-mail backup and preservation protocols. In particular, e-mails were backed up in two distinct ways: on backup tapes and on optical disks.
UBS employees used a program called HP OpenMail, manufactured by Hewlett-Packard,*fn22 for all work-related e-mail communications.*fn23 With limited exceptions, all e-mails sent or received by any UBS employee are stored onto backup tapes. To do so, UBS employs a program called Veritas NetBackup,*fn24 which creates a "snapshot" of all e-mails that exist on a given server at the time the backup is taken. Except for scheduling the backups and physically inserting the tapes into the machines, the backup process is entirely automated.
UBS used the same backup protocol during the entire relevant time period, from 1999 through 2001. Using NetBackup, UBS backed up its e-mails at three intervals: (1) daily, at the end of each day, (2) weekly, on Friday nights, and (3) monthly, on the last business day of the month. Nightly backup tapes were kept for twenty working days, weekly tapes for one year, and monthly tapes for three years. After the relevant time period elapsed, the tapes were recycled.*fn25
Once e-mails have been stored onto backup tapes, the restoration process is lengthy. Each backup tape routinely takes approximately five days to restore, although resort to an outside vendor would speed up the process (at greatly enhanced costs, of course). Because each tape represents a snapshot of one server's hard drive in a given month, each server/month must be restored separately onto a hard drive. Then, a program called Double Mail is used to extract a particular individual's e-mail file. That mail file is then exported into a Microsoft Outlook data file, which in turn can be opened in Microsoft Outlook, a common e-mail application. A user could then browse through the mail file and sort the mail by recipient, date or subject, or search for key words in the body of the e-mail.
Fortunately, NetBackup also created indexes of each backup tape. Thus, Behny was able to search through the tapes from the relevant time period and determine that the e-mail files responsive to Zubulake's ...