Legal Matters	12 Months Ended
Dec. 31, 2011
Legal Matters	(9) Legal Matters On July 31, 2007, the Company was served with a complaint filed in the United States District Court for the Southern District of New York by the Shareholders’ Representative of Proficient Systems, Inc. In connection with the July 2006 acquisition of Proficient, the Company was contingently required to issue up to 2,050,000 shares of common stock based on the terms of an earn-out provision in the merger agreement. In accordance with the terms of the earn-out provision, the Company issued 1,127,985 shares of LivePerson common stock in the second quarter of 2007 to the former shareholders of Proficient. The amended complaint filed by the Shareholders’ Representative, or Plaintiff, on May 12, 2009 alleges that the Company breached the merger agreement by failing to properly account for net annualized revenue, and demands payment of damages on the grounds that substantially all of the remaining contingently issuable earn-out shares should have been paid. The Company believes the claims are without merit. The case proceeded to trial, which ended on November 4, 2010. Post-trial filings were made on November 19, 2010. The Court has still not issued its ruling in this case. In the event that the Court finds in whole or in part for Plaintiff, the Company would be required to pay monetary damages in the amount held by the Court to have been underpaid in the earn-out. The Company is presently unable to reasonably estimate the amount of actual damages, if any, that will be awarded by the Court. If the Court were to find in favor of Plaintiff on every claim at issue in the litigation, the maximum potential damages award would be approximately $6,000. Should the Company be required to pay any damages award, the associated payment would be allocated to goodwill in connection with Proficient acquisition. On November 3, 2010, Gemini IP LLC filed an amended complaint in a suit pending in the United States District Court for the Eastern District of Texas, adding patent infringement allegations against the Company and various other defendants, including LANDesk Software, Inc., Saba Software, Inc., Genesys S.A. d/b/a Genesys Conferencing, Genesys Conferencing, Inc., Avaya Inc., Best Buy Co., Inc., Bomgar Corporation, ConnectWise, Inc., Elsinore Technologies Inc., GFI Software Ltd., GFI USA, Inc., GFI Software Development, Ltd., LogMeIn, Inc., N-able Technologies Incorporated, NTR Global, Venti Solutions, LLC, Zoho Corporation, Zenith Infotech Ltd., International Business Machines Corp., Samsung Electronics America, Inc., Samsung Electronics Co., Ltd., Samsung Telecommunications America, LLC, AT&T, Inc., Sony Corporation, and Sony Corporation of America. On August 26, 2011, Gemini and LivePerson jointly filed a motion asking the Court to dismiss all claims with prejudice. The Court has not yet ruled on that motion. On June 15, 2011, the Company filed suit against Lodsys, LLC, in the United States District Court for the Northern District of Illinois, seeking a declaratory judgment that the Company’s products do not infringe four patents which Lodsys had previously asserted were infringed by the Company’s customers, as well as a declaratory judgment that those four patents are invalid. On July 5, 2011, Lodsys moved to dismiss the Illinois case based on lacking personal jurisdiction, and also countersued the Company and other plaintiffs in similarly-situated declaratory judgment actions, including DriveTime Automotive Group, Inc., ESET, LLC, ForeSee Results, LLC, OpinionLab, Inc., and The New York Times Company, in the United States District Court for the Eastern District of Texas. In the Texas case, Lodsys alleges that the Company infringes one of the patents involved in the co-pending Illinois case, and seeks damages for past infringement, and an injunction against future infringement. The Company believes Lodsys’s claims are without merit. On October 25, 2011 the Court granted the parties’ joint motion to transfer the cases from Illinois to the Eastern District of Wisconsin, and all pending motions were withdrawn, including Lodsys’s pending motion to dismiss. On January 6, 2012 Lodsys filed a motion to dismiss the Wisconsin case, or, in the alternative, for a more definite statement. On January 27, 2012 the Company filed an amended complaint in the Wisconsin case. On February 10, 2012 Lodsys filed a motion to dismiss the Wisconsin case, or, in the alternative, to transfer or stay. On January 23, 2012, the Company moved to dismiss the Texas case in favor of the first-filed Wisconsin case. On February 9, 2012 Lodsys filed its opposition to the Company’s motion, and the Company filed its reply on February 21, 2012. This motion is fully briefed. On February 7, 2012, the Company filed suit against Pragmatus Telecom LLC in the District of Delaware, seeking a declaratory judgment that the Company’s products do not infringe three patents owned by Pragmatus which Pragmatus had previously asserted were infringed by certain of the Company’s customers, as well as a declaratory judgment that those four patents are invalid. Although the Company currently does not expect that the outcome in any of these matters, individually or collectively, will have a material adverse effect on its financial condition or results of operations, litigation is inherently unpredictable. Therefore, judgments could be rendered or settlements entered, that could adversely affect the Company’s operating results or cash flows in a particular period. The Company routinely assesses all of its litigation and threatened litigation as to the probability of ultimately incurring a liability, and records its best estimate of the ultimate loss in situations where it assesses the likelihood of loss as probable. From time to time, the Company is involved in other legal proceedings arising in the ordinary course of its business, which may arise from direct legal claims brought by or against the Company, or from claims brought against the Company’s customers for which the Company has a contractual indemnification obligation.

(9) Legal Matters

On July 31, 2007, the Company was served with a complaint filed in the United States District Court for the Southern District of New York by the Shareholders’ Representative of Proficient Systems, Inc. In connection with the July 2006 acquisition of Proficient, the Company was contingently required to issue up to 2,050,000 shares of common stock based on the terms of an earn-out provision in the merger agreement. In accordance with the terms of the earn-out provision, the Company issued 1,127,985 shares of LivePerson common stock in the second quarter of 2007 to the former shareholders of Proficient. The amended complaint filed by the Shareholders’ Representative, or Plaintiff, on May 12, 2009 alleges that the Company breached the merger agreement by failing to properly account for net annualized revenue, and demands payment of damages on the grounds that substantially all of the remaining contingently issuable earn-out shares should have been paid. The Company believes the claims are without merit. The case proceeded to trial, which ended on November 4, 2010. Post-trial filings were made on November 19, 2010. The Court has still not issued its ruling in this case. In the event that the Court finds in whole or in part for Plaintiff, the Company would be required to pay monetary damages in the amount held by the Court to have been underpaid in the earn-out. The Company is presently unable to reasonably estimate the amount of actual damages, if any, that will be awarded by the Court. If the Court were to find in favor of Plaintiff on every claim at issue in the litigation, the maximum potential damages award would be approximately $6,000. Should the Company be required to pay any damages award, the associated payment would be allocated to goodwill in connection with Proficient acquisition.

On November 3, 2010, Gemini IP LLC filed an amended complaint in a suit pending in the United States District Court for the Eastern District of Texas, adding patent infringement allegations against the Company and various other defendants, including LANDesk Software, Inc., Saba Software, Inc., Genesys S.A. d/b/a Genesys Conferencing, Genesys Conferencing, Inc., Avaya Inc., Best Buy Co., Inc., Bomgar Corporation, ConnectWise, Inc., Elsinore Technologies Inc., GFI Software Ltd., GFI USA, Inc., GFI Software Development, Ltd., LogMeIn, Inc., N-able Technologies Incorporated, NTR Global, Venti Solutions, LLC, Zoho Corporation, Zenith Infotech Ltd., International Business Machines Corp., Samsung Electronics America, Inc., Samsung Electronics Co., Ltd., Samsung Telecommunications America, LLC, AT&T, Inc., Sony Corporation, and Sony Corporation of America. On August 26, 2011, Gemini and LivePerson jointly filed a motion asking the Court to dismiss all claims with prejudice. The Court has not yet ruled on that motion.

On June 15, 2011, the Company filed suit against Lodsys, LLC, in the United States District Court for the Northern District of Illinois, seeking a declaratory judgment that the Company’s products do not infringe four patents which Lodsys had previously asserted were infringed by the Company’s customers, as well as a declaratory judgment that those four patents are invalid. On July 5, 2011, Lodsys moved to dismiss the Illinois case based on lacking personal jurisdiction, and also countersued the Company and other plaintiffs in similarly-situated declaratory judgment actions, including DriveTime Automotive Group, Inc., ESET, LLC, ForeSee Results, LLC, OpinionLab, Inc., and The New York Times Company, in the United States District Court for the Eastern District of Texas. In the Texas case, Lodsys alleges that the Company infringes one of the patents involved in the co-pending Illinois case, and seeks damages for past infringement, and an injunction against future infringement. The Company believes Lodsys’s claims are without merit. On October 25, 2011 the Court granted the parties’ joint motion to transfer the cases from Illinois to the Eastern District of Wisconsin, and all pending motions were withdrawn, including Lodsys’s pending motion to dismiss. On January 6, 2012 Lodsys filed a motion to dismiss the Wisconsin case, or, in the alternative, for a more definite statement. On January 27, 2012 the Company filed an amended complaint in the Wisconsin case. On February 10, 2012 Lodsys filed a motion to dismiss the Wisconsin case, or, in the alternative, to transfer or stay. On January 23, 2012, the Company moved to dismiss the Texas case in favor of the first-filed Wisconsin case. On February 9, 2012 Lodsys filed its opposition to the Company’s motion, and the Company filed its reply on February 21, 2012. This motion is fully briefed.

On February 7, 2012, the Company filed suit against Pragmatus Telecom LLC in the District of Delaware, seeking a declaratory judgment that the Company’s products do not infringe three patents owned by Pragmatus which Pragmatus had previously asserted were infringed by certain of the Company’s customers, as well as a declaratory judgment that those four patents are invalid.

Although the Company currently does not expect that the outcome in any of these matters, individually or collectively, will have a material adverse effect on its financial condition or results of operations, litigation is inherently unpredictable. Therefore, judgments could be rendered or settlements entered, that could adversely affect the Company’s operating results or cash flows in a particular period. The Company routinely assesses all of its litigation and threatened litigation as to the probability of ultimately incurring a liability, and records its best estimate of the ultimate loss in situations where it assesses the likelihood of loss as probable.

From time to time, the Company is involved in other legal proceedings arising in the ordinary course of its business, which may arise from direct legal claims brought by or against the Company, or from claims brought against the Company’s customers for which the Company has a contractual indemnification obligation.