Kathryn S. Lengyel

Securus Technologies, Inc. operates as a profit prison technology company. It connects inmates and family using inmate calling options and video visitation. The firm offers phone services, video services, jail voicemail, money transfer, and email services. The company was founded in 1986 and is headquartered in Dallas, TX.

Stone Holdings, Inc. engages in investing in early-stage businesses in the information, financial services, technology and Internet industries. The company was founded in 1988 and is headquartered in Dallas, TX.

Excel Telecom (dba Excel Telecommunications) is a leading, facilities based provider of a rich suite of high quality, integrated voice and data communications products and services to residential, commercial and carrier customers. Excel offers a wide range of switched and dedicated voice and data services, including domestic and international direct-dial and dial-around long distance, toll-free, wholesale pre-paid long distance and local services, as well as carrier transport, conferencing, hosting and other value-added services, to commercial, carrier and residential customers. Based on its Veraz softswitching platform, Excel has developed and deployed its next generation, IP-based voice and data services, including SIP trunking, hosted IP PBX, IP VPNs and dedicated data services. The Company owns and operates a robust, nationwide Class IV/V VoIP-FGD enabled network that forms a mesh of connectivity across 9 major U.S. metropolitan markets. Consisting of long haul fiber paths, numerous routers, servers and switching equipment, the network provides on-net coverage of virtually every U.S. LATA. Excel also maintains interconnect agreements with more than 300 carriers.