NYSE AMEX: VHC COWEN AND COMPANY 39TH ANNUAL TECHNOLOGY MEDIA TELECOM CONFERENCE JUNE 2, 2011

1. NYSE AMEX: VHCCOWEN AND COMPANY 39TH ANNUAL TECHNOLOGY MEDIA & TELECOM CONFERENCE  JUNE 2, 2011 

3. Agenda Introduction � Company and Team Performance recap and Highlights Market Overview VirnetX Technology Overview VirnetX Licensing Offerings and Litigation Update Financial Update Summary Q and A

4. Company Background VirnetX portfolio includes critical, fundamental and foundational patents, technologies and software for securing real-time communications over the Internet

5. Company Highlights VirnetX Holding Corporation (NYSE Amex: VHC) Headquartered in Scotts Valley, California Market Cap of over $1.30 Billion Experienced management with demonstrated track record Core R&D came over from SAIC, a leading provider of government and defense services Patented technology for securing real-time communications and essential to LTE security standards Large licensing opportunity in IP Telephony, Fixed-Mobile Convergence (FMC), Mobility and Unified Communications

6. Management Team

7. Performance RecapandHighlights

8. VHC Stock Performance � Last 5 Years

9. VHC Stock Performance

10. Stock Performance � Year to Date*

11. Highlights from last 12 months June 15 2010 - Advanced to Russell 3000 Index and Global Index June 16 2010 - Announced one-time special cash dividend of $0.50 per share of the Company�s common stock payable on July 15, 2010 to stockholders of record on July 1, 2010 June 16 2010 � Notified by the United States Patent and Trademark Office (USPTO) that all claims of our U.S. Patent No. 6,502,135 and U.S. Patent No. 7,188,180 are patentable and valid June 30 2010 � Announced that Dr. Robert Short III will take over duties as our Chief Technical Officer replacing Edmund �Gif� Munger who formally retired from active service in order to pursue other interests and spend time with his family August 11 2010 - Filed a complaint against Aastra USA, Inc., Aastra Technologies Ltd., Apple Inc., Cisco Systems, Inc., NEC Corporation, and NEC Corporation of America in the United States District Court for the Eastern District of Texas, Tyler Division with allegations of patent infringement regarding five of our patents and seeking both damages and injunctive relief. October 28 2010 - Retained law firm Wilson Sonsini Goodrich & Rosati as our outside Corporate Counsel

12. Highlights from last 12 months December 2 2010 � Received a new European Security Patent January 12, 2011 - Filed a complaint against Siemens AG, Siemens Corporation, Siemens Communications, Inc., Siemens Enterprise Communications, Inc., Mitel Networks Corporation and Mitel Networks, Inc., in the United States District Court for the Eastern District of Texas, Tyler Division March 15 2011 - Updated Patent Declaration to 3GPP for LTE/4G Security and declared availability of a RAND license upon request April 5 2011 - Granted U.S. Patent No. 7,921,211, Agile Network Protocol for Secure Communications Using Secure Domain Names, by the U.S. Patent and Trademark Office April 5 2011 - Filed papers with the U.S. District Court for the Eastern District of Texas seeking to add allegations that all of the defendants in our two currently-pending patent infringement lawsuits, VirnetX Inc. v. Cisco Systems, Inc., VirnetX Inc. v. Mitel Networks Corporation, infringe our U.S. Patent No. 7,921,211 April 5 2011 - Added Apple�s iPad 2 to the list of alleged infringing products

13. Highlights from last 12 months April 12 2011 - Added Avaya as a defendant in a patent infringement lawsuit currently pending in the United States District Court for the Eastern District of Texas, Tyler Division with allegations of patent infringement regarding three of our patents and seeking both damages and injunctive relief April 21 2011 - Promoted Three to Vice President positions April 26 2011 - Granted U.S. Patent No. 7,933,990, Network Protocol for Secure Communications with Assured System Availability, by the United States Patent and Trademark Office April 28 2011 - Updated our licensing declaration to ETSI under ETSI�s Intellectual Property Rights (IPR) policy at the request of ETSI and agreed to make available, upon request, a non-exclusive patent license under FRAND (fair, reasonable and non-discriminatory terms and conditions, with compensation), to 3GPP members desiring to implement the Technical Specifications identified in our declaration May 17 2011 - Granted U.S. Patent No. 7,945,654, Agile Network Protocol for Secure Communications Using Secure Domain Names, by the United States Patent and Trademark Office May 27 2011 � Cowen and Company initiates VHC stock coverage with �Outperform� rating

14. Market Overview - Enabling New Markets

15. Combined Target Market Opportunity

16. �Access On The Go� � 4G/LTE

18. LTE (Long Term Evolution) Key Drivers Broadband wireless � High speed mobile data access Convergence of technology and networks � Applications working across multiple networks and devices over IP Multimedia System (IMS) Intelligence at the services edge � Policy enforcement and decisions at the network edge - an access-agnostic but access-aware framework Flat all-IP based multi-access core network � Simple, fast, scalable, and enables consistent access-aware policy enforcement and billing Embedded security � Mandatory end to end security across all devices across all networks Wide range of devices � Explosion of devices requiring connectivity like smartphones, computer and consumer electronic devices, such as ultra-portables, gaming devices, cameras, etc

19. Mobile Applications over IMS

20. VirnetX Value Proposition for LTE Portfolio of patents are or may become essential for implementing certain 3GPP (Release 10 or Prior Release) specifications, including 3GPP TS 33.203, �3G security: Access security for IP-based services,� 3GPP TS 33.210, �3G Security: Network Domain Security; IP network layer security� 3GPP TS 33.328, �3G Security: IP Multimedia Subsystem (IMS) media plane security,� 3GPP TS 33.141, �3G Security: Presence service; Security,� 3GPP TS 33.222, �3G Security: Access to network application functions using Hypertext Transfer Protocol over Transport Layer Security (HTTPS),� 3GPP TS 23.003, �3G Core Network and Terminals; Numbering, addressing and identification� 3GPP TS 32.583, �3G Services and System Aspects; Telecommunication management; Home Node B (HNB) Operations, Administration, Maintenance and Provisioning (OAM&P); Procedure flows for Type 1 interface HNB to HNB Management System (HMS)� Non-exclusive license available upon request under fair, reasonable and non- discriminatory terms and conditions, with compensation

21. Technology Overview

22. Gabriel can be a game changer!

23. Vision - Automated VPN Connections

24. Technology Advantages VirnetX�s patented technology provides a seamless, automated security platform which provides secure communication by next-generation Internet-based applications The key benefits and features of our technology include: Seamless and automatic to the user � After a one-time registration, users connect securely on a �zero-click� or �single-click� basis - no cryptographic or password information required Secure data communications � Users create secure networks with people they trust and communicate over a secure channel Control of data at all times � Users can secure and customize their unified communication and collaboration applications with policy-based access and secure presence information Authenticated users � Users know they are communicating with other trusted users that have secure domain names Application-agnostic technology � Provides security at the IP layer of the network by using patented DNS lookup mechanisms to make connections between secure domain names

25. Safe NeighborhoodsTM Uses VirnetX�s GABRIEL Connection Technology� Easily share your data: photos, music, other files

26. License & Service Offerings and Litigation Update

27. License & Service Offerings

28. Security Patent Licensing Model Assumptions

29. Continuing Research and Development at VirnetX 16 U.S. and 16 foreign patents issued; Multiple U.S. and foreign applications pending

30. Some Key Patents in the Portfolio

31. Patent Enforcement Summary VirnetX vs. Cisco Systems, Inc. et al On August 11, 2010, VirnetX filed a complaint against Aastra, Apple Inc., Cisco Systems, Inc., NEC in the United States District Court for the Eastern District of Texas, Tyler Division Includes allegations of patent infringement regarding six patents owned by VirnetX and seeks both damages and injunctive relief Markman Hearing on January 12, 2012 with Jury Trial on November 13, 2012 VirnetX vs. Mitel Networks Corporation et al On January 14, 2011, VirnetX filed a complaint against Mitel Networks, Siemens Enterprise Communications in the United States District Court for the Eastern District of Texas, Tyler Division Includes allegations of patent infringement regarding six patents owned by VirnetX and seeks both damages and injunctive relief On April 12, 2011, VirnetX added Avaya to this lawsuit Includes allegations of patent infringement regarding three patents owned by VirnetX and seeks both damages and injunctive relief

32. Company Financials

33. VirnetX Summary Income Statement

34. VirnetX Summary Balance Sheet & Capitalization

35. Execution of Corporate Strategy Incentivize early licensing targets Assert patent rights for use Build secure domain name registry Run franchise registrar program

36. Company Summary VirnetX Holding Corporation (NYSE Amex: VHC) Headquartered in Scotts Valley, California Market Cap of over $1.30 Billion Experienced management with demonstrated track record Core R&D came over from SAIC, a leading provider of government and defense services Patented technology for securing real-time communications and essential to LTE security standards Large licensing opportunity in IP Telephony, Fixed-Mobile Convergence (FMC), Mobility and Unified Communications