Russ, August & Kabat provides legal services to the Company with respect to its patent litigation filed in May 2017 against Facebook, Inc. in the U.S. District Court for the Southern District of New York relating to several patents within the Company's Mirror Worlds Patent Portfolio (see Note I[4] hereof).  The terms of the Company's agreement with Russ, August & Kabat provide for cash payments on a monthly basis subject to a cap plus a contingency fee ranging between 15% and 24% of the net recovery (after deduction of expenses) depending on the stage of the proceeding in which the result (settlement or judgment) is achieved.  The Company is responsible for all of the expenses incurred with respect to this litigation.

Russ, August & Kabat also provides legal services to the Company with respect to its pending patent litigations filed in April 2014 and December 2014 against Google Inc. and YouTube, LLC in the United States District Court for the Southern District of New York relating to certain patents within the Company's Cox Patent Portfolio (see Note I[3] hereof).  The terms of the Company's agreement with Russ, August & Kabat provide for legal fees on a full contingency basis ranging from 15% to 30% of the net recovery (after deduction of expenses) depending on the stage of the proceeding in which the result (settlement or judgment) is achieved.  The Company is responsible for all of the expenses incurred with respect to this litigation.

Dovel & Luner, LLP provides legal services to the Company with respect to its patent litigation filed in September 2011 against sixteen (16) data networking equipment manufacturers in the U.S. District Court for the Eastern District of Texas, Tyler (see Note I[1] hereof).  The terms of the Company's agreement with Dovel & Luner LLP essentially provide for legal fees on a full contingency basis ranging from 12.5% to 35% (with certain exceptions) of the net recovery (after deduction for expenses) depending on the stage of the preceding in which a result (settlement or judgment) is achieved.  For the three months ended March 31, 2019 and March 31, 2018, the Company incurred aggregate contingent legal fees to Dovel & Luner, LLP with respect to the litigation of $108,000 and $6,277,000, respectively.  The Company is responsible for a certain portion of the expenses incurred with respect to the litigation.

Dovel & Luner, LLP also provided legal services to the Company with respect to the litigation settled in July 2010 against Cisco and several other major data networking equipment manufacturers (see Note I[2] hereof).  The terms of the Company's agreement with Dovel & Luner, LLP with respect to this litigation provided for legal fees of a maximum aggregate cash payment of $1.5 million plus a contingency fee of 24% (based on the settlement being achieved at the trial stage).  As a result of the royalty payments payable quarterly by Cisco in accordance with the Company's settlement and license agreement with Cisco, the Company has an obligation to pay Dovel & Luner, LLP (including local counsel) 24% of such royalties received.  During the three months ended March 31, 2019 and March 31, 2018, the Company did not incur any contingent legal fees to Dovel & Luner, LLP with respect to the litigation.

On February 28, 2013, the Company completed the acquisition of four patents (as well as a pending patent application) from Dr. Ingemar Cox (these patents together with subsequent related patent issuances comprise the Cox Patent Portfolio), a technology leader in digital watermarking content identification, digital rights management and related technologies, for a purchase price of $1,000,000 in cash and 403,226 shares of the Company's common stock.  In addition, the Company is obligated to pay Dr. Cox 12.5% of the net proceeds (after deduction of expenses) generated by the Company from licensing, sale or enforcement of the patents.  Since the acquisition of the patent portfolio from Dr. Cox, the Company has been issued twenty-five (25) additional related patents by the USPTO resulting in an aggregate of twenty-nine (29) patents within the Cox Patent Portfolio.

On May 21, 2013, the Company's wholly-owned subsidiary, Mirror Worlds Technologies, LLC, acquired all of the patents previously owned by Mirror Worlds, LLC (which subsequently changed its name to Looking Glass LLC ("Looking Glass")), consisting of nine issued U.S. patents and five pending applications covering foundational technologies that enable unified search and indexing, displaying and archiving of documents in a computer system (these patents together with subsequent related patent issuances comprise the Mirror Worlds Patent Portfolio). As consideration for the patent acquisition, the Company paid Looking Glass $3,000,000 in cash, and issued 5-year warrants to purchase an aggregate of 1,750,000 shares of the Company's common stock (875,000 shares of common stock at an exercise price of $1.40 per share and 875,000 shares of common stock at an exercise price of $2.10 per share) (the "Looking Glass Warrants").  On June 3, 2014, the Company repurchased the Looking Glass Warrants from Looking Glass at a cost of $505,000.  In addition, Recognition Interface, LLC ("Recognition"), an entity that financed the commercialization of the patent portfolio prior to its sale to Mirror Worlds, LLC and also retained an interest in the licensing proceeds of the patent portfolio held by Mirror Worlds, LLC, and an affiliated entity also received warrants to purchase an aggregate of 1,250,000 shares of the Company's common stock (500,000 shares at an exercise price of $2.05 per share, 375,000 shares at an exercise price of $2.10 per share and 375,000 shares at an exercise price of $1.40 per share).  All such warrants were exercised by Recognition (and its affiliate) as of January 2017, resulting in aggregate proceeds to the Company of $2,337,000.

As part of the acquisition of the Mirror Worlds Patent Portfolio, the Company also entered into an agreement with Recognition pursuant to which Recognition received from the Company an interest in the net proceeds realized from the monetization of the Mirror Worlds Patent Portfolio, as follows: (i) 10% of the first $125 million of net proceeds; (ii) 15% of the next $125 million of net proceeds; and (iii) 20% of any portion of the net proceeds in excess of $250 million.  Since entering into the agreement with Recognition in May 2013, the Company has paid Recognition an aggregate of $3,127,000 with respect to such net proceeds interest related to the Mirror Worlds Patent Portfolio.  No such payments were made by the Company to Recognition during the three months ended March 31, 2019 and March 31, 2018.

On December 29, 2017, the Company acquired from M2M and IoT Technologies, LLC ("M2M") the M2M/IoT Patent Portfolio consisting of twelve (12) issued U.S. patents relating to, among other things, the enabling technology for authenticating and using embedded SIM cards in next generation IoT, Machine-to-Machine, and other mobile devices, including smartphones, tablets and computers as well as automobiles and drones.  The Company paid $1,000,000 to acquire the M2M/IoT Patent Portfolio from M2M and has an obligation to pay M2M 14% of the first $100 million of net proceeds (after deduction of expenses) and 5% of net proceeds greater than $100 million from Monetization Activities (as defined) related to the patent portfolio. In addition, M2M will be entitled to receive from the Company $250,000 of additional consideration upon the occurrence of certain future events related to the patent portfolio.  Since the acquisition of the patent portfolio from M2M, the Company has been issued nine additional related patents by the USPTO resulting in an aggregate of twenty-one (21) issued U.S. patents.

The Company currently has two facility operating leases with remaining lease terms of six months to fourteen months. The Company leases its principal office space in New York City at a monthly base rent of approximately $3,900 which lease expires on May 31, 2020. The Company also leases office space in New Canaan, Connecticut expiring on September 30, 2019 at a base rent (inclusive of utilities) of $7,750 per month (increasing $100 per month each year), which is subject to annual adjustments to reflect increases in real estate taxes and operating expenses.

Under ASC 842 (see Note B[15] hereof), operating lease expense is generally recognized evenly over the term of the lease. Leases with an initial term of twelve months or less are not recorded on the balance sheet. For lease arrangements entered into or reassessed after the adoption of ASC 842, the Company combines the lease and non-lease components in determining the right-of-use ("ROU") assets and related lease obligation.

Activity related to the Company's operating leases was as follows:

The Company's operating lease agreements generally do not provide an implicit borrowing rate; therefore, an internal incremental borrowing rate was determined based on information available for purposes of determining the present value of lease payments. The Company used an incremental borrowing rate of 5.5% at January 1, 2019 for all leases that commenced prior to that date. ROU lease assets and related lease obligations for the Company's operating leases were recorded in the condensed consolidated balance sheet as follows:

Future lease payments included in the measurement of lease liabilities on the unaudited condensed consolidated balance sheet as of March 31, 2019, were as follows: