Inter Partes Review of
`U.S. Patent No. 9,794,070
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`_____________________
`
`Zoom Video Communications, Inc.,
`Petitioner,
`
`v.
`
`Cyph, Inc.,
`Patent Owner.
`______________________________________________________________
`
`Case No. IPR2023-00142
`
`U.S. Patent No. 9,794,070
`Issue Date: October 17, 2017
`
`
`
`
`PETITION FOR INTER PARTES REVIEW OF
`U.S. PATENT NO. 9,794,070
`
`
`
`
`
`
`
`
`
`
`
`
`
`

`

`Inter Partes Review of
`U.S. Patent No. 9,794,070
`TABLE OF CONTENTS
`
`Page
`
`V.
`
`INTRODUCTION ........................................................................................ 1
`I.
`GROUNDS FOR STANDING (37 C.F.R. § 42.104(A)) ............................... 2
`II.
`IDENTIFICATION OF CHALLENGES (37 C.F.R. § 42.104(B))................ 2
`III.
`IV. TECHNOLOGY BACKGROUND............................................................... 3
`A.
`Cryptography and Encryption ............................................................. 4
`B.
`Ephemeral Communication ................................................................. 4
`C. Web-Based Communications and Devices Used for Web-Based
`Communications ................................................................................. 6
`THE ’070 PATENT ...................................................................................... 8
`A.
`Specification ....................................................................................... 8
`B.
`Prosecution History........................................................................... 14
`VI. PERSON OF ORDINARY SKILL IN THE ART (“POSA”) ...................... 16
`VII. CLAIM CONSTRUCTION ........................................................................ 16
`VIII. OVERVIEW OF THE PRIOR ART ........................................................... 17
`A. Wauters (Ex. 1005) ........................................................................... 17
`B.
`Kaushik (Ex. 1006) ........................................................................... 19
`C.
`Gudjonsson (Ex. 1007) ..................................................................... 20
`IX. GROUNDS ................................................................................................. 23
`A. Ground 1: Claims 1 and 2 Are Obvious Over Wauters in View of
`Gudjonsson ....................................................................................... 23
`1.
`Obviousness to a POSA .......................................................... 23
`a. Motivation to Combine ................................................. 23
`b.
`Reasonable Expectation of Success ............................... 25
`Claim 1 ................................................................................... 27
`a.
`[1.0] “A method comprising:” ....................................... 27
`
`2.
`
`
`
`
`
`i
`
`
`
`

`

`b.
`
`c.
`
`d.
`
`e.
`
`f.
`
`g.
`
`h.
`
`i.
`
`[1.1a] “sending a request, by a first user on a first device,
`to a server,” ................................................................... 27
`[1.1b] “the request comprising requesting the server open
`an ephemeral communication session with a second user
`on a second device;” ..................................................... 31
`[1.2] “allocating resources, by the server, to begin the
`ephemeral communication session between the first user
`and the second user;” .................................................... 33
`[1.3a] “generating a unique ephemeral communication
`session identifier by the server for each ephemeral
`communication session and” ......................................... 37
`[1.3b] “transmitting the unique ephemeral
`communication session identifier to the first user;” ....... 39
`[1.4] “transmitting, by the first user, the unique
`ephemeral communication session identifier to the
`second user using a second communication channel;” .. 40
`[1.5] “connecting, by the second user, to the first user
`through the ephemeral communication session using the
`unique ephemeral communication session identifier;
`and;” ............................................................................. 41
`[1.6] “connecting, by the first user, to the second user
`through the ephemeral communication session using the
`unique ephemeral communication session identifier.”... 43
`Claim 2 ................................................................................... 43
`a.
`[2.0] “The method of claim 1, wherein:” ....................... 43
`b.
`[2.1] “connecting, by the second user, to the first user
`through the ephemeral communication session includes
`connecting to the server; and;” ...................................... 43
`[2.2] “connecting, by the first user, to the second user
`through the ephemeral communication session includes
`connecting to the server.” .............................................. 47
`Ground 2: Claims 1 and 2 Are Obvious Over Kaushik in View of
`Gudjonsson ....................................................................................... 47
`1.
`Obviousness to a POSA .......................................................... 47
`a. Motivation to Combine ................................................. 47
`b.
`Reasonable Expectation of Success ............................... 49
`Claim 1 ................................................................................... 50
`
`c.
`
`B.
`
`3.
`
`2.
`
`
`
`
`
`ii
`
`
`
`

`

`a.
`b.
`
`c.
`
`d.
`
`e.
`
`f.
`
`g.
`
`h.
`
`i.
`
`[1.0] “A method comprising:” ....................................... 50
`[1.1a] “sending a request, by a first user on a first device,
`to a server,” ................................................................... 51
`[1.1b] “the request comprising requesting the server open
`an ephemeral communication session with a second user
`on a second device;” ..................................................... 53
`[1.2] “allocating resources, by the server, to begin the
`ephemeral communication session between the first user
`and the second user;” .................................................... 55
`[1.3a] “generating a unique ephemeral communication
`session identifier by the server for each ephemeral
`communication session and” ......................................... 57
`[1.3b] “transmitting the unique ephemeral
`communication session identifier to the first user;” ....... 59
`[1.4] “transmitting, by the first user, the unique
`ephemeral communication session identifier to the
`second user using a second communication channel;” .. 60
`[1.5] “connecting, by the second user, to the first user
`through the ephemeral communication session using the
`unique ephemeral communication session identifier;
`and;” ............................................................................. 61
`[1.6] “connecting, by the first user, to the second user
`through the ephemeral communication session using the
`unique ephemeral communication session identifier.”... 63
`Claim 2 ................................................................................... 63
`a.
`[2.0] “The method of claim 1, wherein:” ....................... 63
`b.
`[2.1] “connecting, by the second user, to the first user
`through the ephemeral communication session includes
`connecting to the server; and;” ...................................... 63
`[2.2] “connecting, by the first user, to the second user
`through the ephemeral communication session includes
`connecting to the server.” .............................................. 65
`X. NO SECONDARY CONSIDERATIONS................................................... 66
`XI. DISCRETIONARY DENIAL IS NOT APPROPRIATE ............................ 66
`A.
`Advanced Bionics and Becton, Dickinson Factors Do Not Support
`Discretionary Denial ......................................................................... 66
`Fintiv Factors Do Not Favor Discretionary Denial ............................ 68
`
`3.
`
`c.
`
`B.
`
`
`
`
`
`iii
`
`
`
`

`

`1.
`
`2.
`
`3.
`
`4.
`
`First Factor: whether a stay exists or is likely to be granted if a
`proceeding is instituted ........................................................... 68
`Second Factor: proximity of the court’s trial date to the
`Board’s projected statutory deadline for a final written decision
`................................................................................................ 69
`Third Factor: investment in the parallel proceeding by the court
`and the parties ......................................................................... 70
`Fourth Factor: overlap between issues raised in the petition and
`in the parallel proceeding ........................................................ 70
`Fifth Factor: whether the petitioner and the defendant in the
`parallel proceeding are the same party .................................... 70
`Sixth Factor: other circumstances that impact the Board’s
`exercise of discretion, including the merits ............................. 70
`General Plastic Does Not Apply....................................................... 71
`C.
`XII. MANDATORY NOTICES (37 C.F.R. § 42.8)............................................ 71
`A.
`Real Party-In-Interest ........................................................................ 71
`B.
`Related Matters ................................................................................. 71
`C.
`Lead and Back-Up Counsel and Service Information ........................ 71
`XIII. PAYMENT OF FEES (37 C.F.R. §§ 42.15(A) & 42.103) .......................... 72
`XIV. CONCLUSION .......................................................................................... 73
`
`
`
`5.
`
`6.
`
`
`
`
`
`iv
`
`
`
`

`

`TABLE OF AUTHORITIES
`
` Page(s)
`
`Cases
`Advanced Bionics, LLC v. Med-El Elektromedizinische Geräte GmbH,
`IPR2019-01469 (P.T.A.B. Feb. 13, 2020) ........................................................ 66
`Becton, Dickinson, & Co. v. B. Braun Melsungen AG,
`IPR2017-01586 (P.T.A.B. Dec. 15, 2017)........................................................ 66
`
`Gen. Plastic Indus. Co. v. Canon Kabushiki Kaisha,
`IPR2016-01357 (P.T.A.B. Sept. 6, 2017) ......................................................... 71
`Phillips v. AWH Corp.,
`415 F.3d 1303 (Fed. Cir. 2005) ........................................................................ 17
`Samsung Elecs. Co. v. Staton Techiya, LLC,
`IPR2022-00302 (P.T.A.B. July 11, 2022) ........................................................ 69
`Sand Revolution II, LLC v. Continental Intermodal Group-Trucking LLC,
`IPR2019-01393 (P.T.A.B. June 16, 2020) ........................................................ 69
`Statutes
`35 U.S.C. § 102 .............................................................................................. 17, 19
`35 U.S.C. § 103 ............................................................................................ 2, 3, 15
`Other Authorities
`Interim Procedure for Discretionary Denials in AIA Post-Grant
`Proceedings with Parallel District Court Litigation
`(USPTO June 21, 2022) ....................................................................... 68, 69, 70
`
`
`
`
`
`
`
`v
`
`
`
`

`

`TABLE OF EXHIBITS
`
`Exhibit No. Description
`1001
`U.S. Patent No. 9,794,070 (“’070 patent”)
`
`1002
`
`1003
`
`1004
`
`1005
`
`1006
`
`File History for the ’070 patent (“’070 patent FH”)
`
`Declaration of Dr. Thomas Ristenpart (“Ristenpart Decl.”)
`
`Curriculum Vitae of Dr. Thomas Ristenpart
`
`February 19, 2009 Snapshot of Robin Wauters, TinyChat Makes
`Creating Disposable Chat Rooms A Breeze, TechCrunch (Feb. 18,
`2009), archived at the Internet Archive’s Wayback Machine at
`https://web.archive.org/web/20090219092443/http://www.techcru
`nch.com/2009/02/18/tinychat-makes-creating-disposable-chat-
`rooms-a-breeze/ (“Wauters”)
`
`June 24, 2009 Snapshot of Kaushik, Create temporary and
`disposable chat rooms with Stinto, InstantFundas (Nov. 24, 2008),
`archived at the Internet Archive’s Wayback Machine at
`https://web.archive.org/web/20090624021641/http:/www.instantfu
`ndas.com/2008/11/create-temporary-and-disposable-chat.html
`(“Kaushik”)
`
`1007
`
`U.S. Patent No. 6,564,261 (“Gudjonsson”)
`
`1008
`
`1009
`
`Gustavus J. Simmons, Symmetric and Asymmetric Encryption,
`Vol. 11, No. 4 ACM Computing Surveys 305-330 (Dec. 1979),
`available at https://dl.acm.org/doi/10.1145/356789.356793
`
`Jennifer Charteris, Sue Gregory, & Yvonne Masters, Snapchat
`‘selfies’: The case of disappearing data, Rhetoric and Reality:
`Critical perspectives on educational technology, Proceedings of
`ascilite Dunedin 2014, pp. 389-93, available at
`https://ascilite2014.otago.ac.nz/files/concisepapers/47-
`Charteris.pdf
`
`
`
`
`
`vi
`
`
`
`

`

`Exhibit No. Description
`December 21, 2008 Snapshot of “Privacy Policy” webpage of the
`stinto.net website, archived at the Internet Archive’s Wayback
`Machine at
`https://web.archive.org/web/20081221154244/http://www.stinto.n
`et:80/datenschutz
`
`1010
`
`1011
`
`1012
`
`1013
`
`1014
`
`1015
`
`1016
`
`January 24, 2009 Snapshot of “About” webpage of the stinto.net
`website, archived at the Internet Archive’s Wayback Machine at
`http://web.archive.org/web/20090124112853/http://stinto.net:80/a
`bout
`
`Jason Fitzpatrick, Stinto Generates Disposable Chat Rooms,
`LifeHacker (Nov. 26, 2008), available at
`https://lifehacker.com/stinto-generates-disposable-chat-rooms-
`5099130
`
`Bright Hub, Review of Stinto – A Browser-Based Temporary Chat
`Room Application (Dec. 26, 2008), available at
`https://www.brighthub.com/environment/green-
`computing/articles/21594/
`
`Scott Gilbertson, TinyChat: Disposable, Web-Based Chat Anyone
`Can Use, Wired (Feb. 19, 2009), available at
`https://www.wired.com/2009/02/tinychat-dispos/
`
`June 27, 2013 Snapshot of azim, TinyChat: Online Chat Rooms
`Without Registering, MUO (Feb. 17, 2009), archived at the
`Internet Archive’s Wayback Machine at
`https://web.archive.org/web/20130627122802/https://www.makeu
`seof.com/tag/tinychat-create-free-chatroom/
`
`February 21, 2009 Snapshot of Suganya, Chat With Your Friends
`Using TinyChat When Messengers Are Blocked At Your
`Office/School/University, Tech Dreams (February 20, 2009),
`archived at the Internet Archive’s Wayback Machine at
`https://web.archive.org/web/20090221191830/https://www.techdr
`eams.org/general/tinychat-%E2%80%93-an-unblocked-
`disposable-chat-even-at-your-office/1558-20090220
`
`
`
`
`
`vii
`
`
`
`

`

`Exhibit No. Description
`December 18, 2014 Snapshot of “Help” webpage of the
`chattory.com website, archived at the Internet Archive’s Wayback
`Machine at
`http://web.archive.org/web/20141218122550/http://www.chattory.
`com/#
`
`1017
`
`Bazara I.A. Barry & Fatma M. Tom, Instant Messaging:
`Standards, Protocols, Applications, and Research Directions, in
`INTERNET POLICIES AND ISSUES, VOL. 7 1-15 (Chapter 8) (B.G.
`Kutais ed., Nova Science Publishers, Inc. 2010), available at
`https://www.researchgate.net/publication/280307922_Instant_Mes
`saging_Standards_Protocols_Applications_and_Research_Directio
`ns
`
`Tom Keating, Yahoo Messenger for the Web launches,
`TMCnet.com (May 2, 2007), available at
`https://blog.tmcnet.com/blog/tom-keating/news/yahoo-messenger-
`for-the-web-launches.asp
`
`Bogdan Popa, Yahoo Launches Web-Based Yahoo Messenger,
`Softpedia News (May 3, 2007), available at
`https://news.softpedia.com/news/Yahoo-Launches-Web-Based-
`Yahoo-Messenger-53796.shtml
`
`Adam Pash, Chat with AIM, MSN, Yahoo, and other contacts over
`Google Talk, LifeHacker (Aug. 14, 2007), available at
`https://lifehacker.com/chat-with-aim-msn-yahoo-and-other-
`contacts-over-goog-289097
`
`Peter Cohen, Flash-based ‘AIM Express’ debuts, Macworld (Aug.
`20, 2008), available at
`https://www.macworld.com/article/192065/aimexpress.html
`
`Karl Gechlik, AIM Express lets you use IM without installing a
`client, MUO (June 21, 2008), available at
`https://www.makeuseof.com/tag/aim-express-lets-you-use-im-
`without-installing-a-client/
`
`1018
`
`1019
`
`1020
`
`1021
`
`1022
`
`1023
`
`
`
`
`
`viii
`
`
`
`

`

`Exhibit No. Description
`AskVG.com, Windows Live Web Messenger: Web Based WLM,
`No Download or Installation Required (Oct. 15, 2009), available
`at https://www.askvg.com/windows-live-web-messenger-web-
`based-wlm-no-download-or-installation-required/
`
`1024
`
`1025
`
`1026
`
`1027
`
`1028
`
`1029
`
`1030
`
`1031
`
`1032
`
`April 3, 2013 Snapshot of tlk.io website, archived at the Internet
`Archive’s Wayback Machine at
`https://web.archive.org/web/20130403162621/http://tlk.io/
`
`August 1, 2014 Snapshot of tlk.io website, archived at the Internet
`Archive’s Wayback Machine at
`https://web.archive.org/web/20140801172659/http://tlk.io/
`
`November 23, 2014 Snapshot of Sagar Karira, Create Your Own
`Chat Room In Seconds With tlk.io, FossBytes (Nov. 11, 2014),
`archived at the Internet Archive’s Wayback Machine at
`https://web.archive.org/web/20141123102452/https://fossbytes.co
`m/chat-talk-discuss-online-without-hassle-tlk-io/
`
`Christian Dewes, Arne Wichmann, & Anja Feldmann, An analysis
`of Internet chat systems, IMC ’03, Proceedings of the 3rd ACM
`SIGCOMM Conference on Internet Measurement, pp. 51–64 (Oct.
`2003), available at https://dl.acm.org/doi/10.1145/948205.948214
`
`Michael Stephens, Tools from “Web 2.0 & Libraries: Best
`Practices for Social Software” Revisited, 5 Library Technology
`Reports 15-31 (Chapter 2) (Sept.-Oct. 2007), available at
`https://journals.ala.org/index.php/ltr/article/view/4822/5778
`
`U.S. Patent No. 7,562,116 (“Barsness”)
`
`U.S. Patent No. 7,912,903 (“Shah”)
`
`J. Oikarinen & D. Reed, Network Working Group Request for
`Comments: 1459, Internet Relay Chat Protocol (May 1993),
`available at https://datatracker.ietf.org/doc/pdf/rfc1459
`
`
`
`
`
`ix
`
`
`
`

`

`Exhibit No. Description
`Raymond B. Jennings III et al., A Study of Internet Instant
`Messaging and Chat Protocols, Vol. 20, Issue 4 IEEE Network
`pp. 16–21 (July/August 2006), available at
`https://ieeexplore.ieee.org/document/1668399
`
`1033
`
`U.S. Patent Application Publication No. 2002/0191797
`(“Perlman”)
`
`Cyph, Inc. v. Zoom Video Communications, Inc., No. 22-cv-
`00561-JSW, Dkt. No. 74 (N.D. Cal. Oct. 7, 2022), Dkt. No. 75
`(N.D. Cal. Oct. 11, 2022).
`
`Excerpts from Microsoft Computer Dictionary (Microsoft Press,
`5th ed. 2002)
`
`Table N/A—U.S. District Courts–Combined Civil and Criminal
`Federal Court Management Statistics (June 30, 2022),
`https://www.uscourts.gov/statistics/table/na/federal-court-
`management-statistics/2022/06/30-2
`
`Cyph, Inc. v. Zoom Video Communications, Inc., No. 21-cv-
`03027-RM-MEH, Dkt. No. 32 (D. Co. Jan. 27, 2022)
`
`Simon Singh, THE CODE BOOK: THE SCIENCE OF SECRECY FROM
`ANCIENT EGYPT TO QUANTUM CRYPTOGRAPHY (First Anchor
`Books Ed., Sept. 2000) (“The Code Book”)
`
`J. Fingas, Google+ Hangouts app hands-on, Engadget (May 15,
`2013)), available at https://www.engadget.com/2013-05-15-
`google-hangouts-app-hands-on.html
`
`1034
`
`1035
`
`1036
`
`1037
`
`1038
`
`1039
`
`1040
`
`
`
`
`
`
`
`x
`
`
`
`

`

`
`
`I.
`
`INTRODUCTION
`U.S. Patent No. 9,794,070 (the “’070 patent”) pertains to alleged advances in
`
`encryption technology for digital communications, such as chats, phone calls, and
`
`videoconferences. The purported insight of the ’070 patent is that available
`
`encryption methods are difficult to use, but information exchanged during digital
`
`communications can be safeguarded against disclosure by using an “ephemeral”
`
`communication channel—which is only open for a limited period—in combination
`
`with a “unique” identifier for each communication session so that the identifier is
`
`of no use once the associated ephemeral communication session expires.
`
`But as of January 7, 2015—the earliest possible priority date of the ’070
`
`patent—these ideas were not new. Snapchat was launched in 2011 with
`
`ephemerality as its cornerstone, and it was not alone. Rather, long before 2015,
`
`there existed multiple web-based communications services that used ephemerality
`
`as a safeguard, including several relying on unique identifiers as claimed. Far from
`
`reciting a patentable invention, the challenged claims seek to lay claim to a
`
`combination of widely-used technologies. As described in detail below with
`
`supporting testimony from Dr. Thomas Ristenpart, these technologies were well
`
`known and documented years before the ’070 patent, and it was obvious to
`
`combine them to predictably result in the claimed methods.
`
`1
`
`

`

`
`
`The Examiner, however, was not given the opportunity to consider the
`
`references discussed in this Petition, nor any analogous prior art. Indeed, not even
`
`a single Information Disclosure Statement (IDS) was filed by Applicant during
`
`prosecution—all of the references considered during prosecution were located by
`
`the Examiner, without help from Applicant. Those unassisted searches did not
`
`locate the art discussed below, which art demonstrates that the challenged claims
`
`are unpatentable obvious combinations of well-known elements. Because this
`
`Petition demonstrates a reasonable likelihood that the challenged claims are
`
`obvious, Petitioner respectfully requests that trial be instituted.
`
`II. GROUNDS FOR STANDING (37 C.F.R. § 42.104(a))
`Petitioner certifies that the patent for which review is sought is available for
`
`inter partes review and that the Petitioner is not barred or estopped from requesting
`
`an inter partes review challenging the patent claims on the grounds identified in
`
`this Petition.
`
`III.
`
`IDENTIFICATION OF CHALLENGES (37 C.F.R. § 42.104(b))
`Petitioner requests that the Board institute inter partes review of the
`
`challenged claims on the following grounds:
`
`Ground 1: Claims 1 and 2 are unpatentable under 35 U.S.C. § 103 as
`
`obvious over Wauters (Ex. 1005) in view of Gudjonsson (Ex. 1007).
`
`2
`
`

`

`
`
`Ground 2: Claims 1 and 2 are unpatentable under 35 U.S.C. § 103 as
`
`obvious over Kaushik (Ex. 1006) in view of Gudjonsson (Ex. 1007).
`
`IV. TECHNOLOGY BACKGROUND
`On its face, the ’070 patent purports to relate to encryption—it is entitled
`
`“Method of Ephemeral Encrypted Communications”—but the claims do not
`
`require any particular encryption be used.1 Ex. 1001, Title; Claims 1–2. Instead,
`
`the claims focus on the temporary, or “ephemeral” nature of the communications,
`
`and on the use of a “unique” identifier used by participants in the communication
`
`to provide some measure of security over the communications. Id., Claims 1–2.
`
`It is these features that the ’070 patent touts as being useful in keeping
`
`exchanges like those described in Figure 4 of the patent from falling into the wrong
`
`hands. See id., Fig. 4 (in response to the text message “hey baby I’m tryin to cheat
`
`on my wife tonite. u down?”, the recipient provides a Cyph link and responds “uh
`
`… dude, just cyph me”). Although not limited to exchanges between computing
`
`devices connected through the Internet, the purported inventions of the ’070 patent
`
`are described as suitable for use in such web-based communications, and the
`
`claims require the involvement of at least two devices and a server. Petitioner
`
`provides background on these various concepts below.
`
`
`1 All emphasis added unless otherwise noted.
`
`3
`
`

`

`
`
`A. Cryptography and Encryption
`Cryptography is the science, and art, of secret writing. Cryptography seeks
`
`to prevent an unauthorized and unintended receiver from determining the content
`
`of the message being communicated. Ex. 1008, 2.
`
`Encryption is an application of cryptography. In short, encryption is the
`
`process of scrambling a message; decryption is the process of unscrambling (or
`
`recovering) the scrambled message. Id., 3.
`
`According to the ’070 patent, when sensitive information is passed across a
`
`public network such as the Internet, “the information can be transmitted over a
`
`secure transmission connection provided by an encryption system.” Ex. 1001,
`
`1:64–2:6. The ’070 patent also explains that as of the time of the invention, ways
`
`to compromise conventional encryption systems were well known and frequently
`
`used. See id., 2:17–29. The ’070 patent thus turns its focus to other tools to
`
`protect communications, including ephemerality.
`
`Ephemeral Communication
`B.
`When two people speak to each other face-to-face, with no recording
`
`devices present, that is an ephemeral communication. It lasts only so long as the
`
`two talk. Non-ephemeral communications such as written letters have also long
`
`existed, as has the desire to make these communications less permanent, reflected
`
`4
`
`

`

`
`
`in the popular culture concept of “burn after reading” to avoid disclosure of a
`
`message.
`
`In digital communications, the preservation of a communication may also be
`
`desired in some circumstances, but not others. Ex. 1003, ¶ 36; Ex. 1009, 1–2.
`
`“Ephemeral messaging with disappearing data enables users to capture and share
`
`temporary moments rather than posting more permanent images . . . . Information
`
`becomes both disposable and short term.” Ex. 1009, 1. A well-known example of
`
`an ephemeral digital communication platform is Snapchat. Ex. 1003, ¶ 36.
`
`Snapchat launched in 2011, long before the priority date of the ’070 patent.
`
`Ex. 1009, 2; Ex. 1003, ¶ 36. Snapchat “facilitates the transmission of images and
`
`script to individuals or groups with a time limit of up to 10 seconds before the
`
`image disappears.” Ex. 1009, 2; Ex. 1003, ¶ 36.
`
`Other ephemeral digital communication platforms were well known in the
`
`art before the earliest priority date of the ’070 patent. For example, Stinto, a web
`
`browser-based temporary and disposable chat room application, became available
`
`in late 2008. Ex. 1006; see also, e.g., Exs. 1010–1013. TinyChat, available by
`
`early 2009, let users create a web-based, disposable chat room. Ex. 1005, 4; see
`
`also, e.g., Exs. 1014–1016. “Using a Mission Impossible tagline of ‘This message
`
`will self destruct,’” a messaging application called iDelete was released in March
`
`2013. Ex. 1009, 2 (internal quotation marks modified). Google Talk was designed
`
`5
`
`

`

`
`
`to “disappear after 24 hours when the history is turned off.” Ex. 1040, 2. In 2014,
`
`another application called Wickr “explicitly market[ed] itself on its capacity to
`
`disappear.” Ex. 1009, 2. Around the same time, another web browser-based
`
`application called Chattory allowed users to create a temporary chat room on the
`
`website. Ex. 1017, 1–2.
`
`C. Web-Based Communications and Devices Used for Web-Based
`Communications
`Web-based communications, and applications that facilitate web-based
`
`communications such as chat room applications, were developed by the 1990s.
`
`Ex. 1018, 3. Many years before 2015, several web-based chat applications were in
`
`widespread public use, including Yahoo Messenger for the Web (launched in
`
`2007), Google Talk (available in 2007), AIM Express (launched in 2008), Stinto
`
`(available in 2008), TinyChat (available in 2009), Windows Live Web Messenger
`
`(available in 2009), tlk.io (available in 2013), and Chattory (available in 2014).
`
`See, e.g., Exs. 1005–1006, 1010–1017, 1019–1027; Ex. 1003, ¶¶ 37, 41; see also
`
`Exs. 1028–1029.
`
`Several of these web-based chat applications required a unique identifier to
`
`allow the initiator of the chat to connect with others. Specifically, TinyChat,
`
`Stinto, Chattory, and tlk.io used a website address (or URL of a website) as a
`
`unique identifier assigned to a particular chat session (or channel). E.g., Exs. 1005
`
`and 1015 (TinyChat), 1006 and 1013 (Stinto), 1017 (Chattory), 1025–1027 (tlk.io).
`
`6
`
`

`

`
`
`Web-based chat applications employ the client-server model, as most web-
`
`based systems do, to allow users to open a chat session and exchange messages
`
`using web browsers. Ex. 1003, ¶ 44; Ex. 1018, 6. The client-server model is a
`
`distributed application structure that partitions tasks or workloads between the
`
`providers of a resource or service (called servers) and service requesters (called
`
`clients). Ex. 1003, ¶ 44; Ex. 1030, 4:34–52 (“In networked systems, a client is
`
`usually a computer that accesses shared network resources provided by another
`
`computer (i.e., a server). … A computer acting as a server makes resources
`
`available to computers acting as workstations on the network.”); see also Ex. 1031,
`
`Fig. 2; 10:11–43. A central server (or a network of servers) may be connected to,
`
`and serve, multiple clients, as illustrated below:
`
`7
`
`

`

`
`
`
`
`Ex. 1018, Fig. 4; Ex. 1030, Fig. 6. Clients and servers communicate over a
`
`communication network such as the Internet. Ex. 1030, 4:37–38; Ex. 1003, ¶ 46.
`
`V. THE ’070 PATENT
`Specification
`A.
`The ’070 patent issued on October 17, 2017, from a U.S. application filed on
`
`August 31, 2015, which claims priority to a U.S. provisional application filed on
`
`January 7, 2015.2
`
`
`2 For the purposes of this proceeding, Petitioner assumes January 7, 2015 as the
`
`’070 patent’s effective filing date. Petitioner reserves the right to contest this or
`
`any earlier priority date in this and in any related proceedings.
`
`8
`
`

`

`
`
`The ’070 patent purports to be “generally relate[d] to cryptography, and,
`
`more particularly, to a method of ephemeral encrypted communication.” Ex. 1001,
`
`1:60–62. According to the inventors, “[c]onventional encryption systems are often
`
`difficult to use” and can be defeated by “well known … techniques.” Id., 2:7–29.
`
`The ’070 patent does not purport to describe any new type of, or improvement to,
`
`encryption, but rather is focused on the desire to “reduce exposure to an encryption
`
`system’s private information and provide an ephemeral communication channel,
`
`thereby reducing the potential attack surface and potential exposure of participants
`
`employing such an encryption system.” Id.
`
`The ’070 patent relies on several steps for reducing the exposure and
`
`susceptibility of digital communications to an attack. First, a first user requests
`
`that the server open an ephemeral communication session with a second user. Id.,
`
`2:33–55. Next, the server generates a “unique ephemeral communication session
`
`identifier” and provides it to the first user. Id. The first user then transmits that
`
`unique ephemeral communication session identifier to the second user “using a
`
`second communication channel.” Id. Lastly, the second user is then connected to
`
`the first user in the ephemeral communication session by using the provided
`
`unique identifier. Id. Consistent with this description, the challenged claims all
`
`require an “ephemeral” communication session, and a “unique” session identifier
`
`to access the ephemeral session. Id., Claims 1–2.
`
`9
`
`

`

`
`
`The described method can be operated using a system built upon a client-
`
`server model discussed above. Ex. 1001, 10:8–13 (“The computing system can
`
`include client and servers. A client and server are generally remote from each
`
`other and typically interact through a communication network.”); see Section IV.C,
`
`above. In the context of the purported invention, any generic “computing device”
`
`can be used as a server. Ex. 1001, 3:56–64 (“a Server (e.g., a computing device
`
`shown in FIGS. 7 and 8)”), 7:50–62 (“The computing device … may be
`
`implemented as a standard server[.]”); see also Ex. 1003, ¶ 54.
`
`As an exemplary embodiment, the ’070 patent describes a web-based
`
`messaging service called CyphTM (the “Cyph application”). Ex. 1001, 3:37–4:30;
`
`Figs. 2–6. As shown in Figure 2, annotated below, the first user visits the website
`
`https://cyph.com (red) and requests to open a new chat session on the Web, by
`
`clicking on the “Start private chat” button (orange) provided on that website:
`
`
`
`10
`
`

`

`
`
`Ex. 1001, Fig. 2 (annotated); 3:58–64 (“Device 1a … associated with a first user
`
`(e.g., Alice) requests opening an ephemeral communication session (e.g., on the
`
`Cyph™ secure messaging platform, as shown in FIG. 2) on a Server … with a
`
`second user (e.g., Bob).”). The server can be “e.g., a computing device shown in
`
`FIGS. 7 and 8.” Id.
`
`In response, the Cyph application generates a communication session
`
`identifier in the form of a URL3 or a link to that URL, as shown in Figure 3:
`
`
`3 The acronym “URL” is typically understood to refer to a “uniform resource
`
`locator,” i.e., a website address. Ex. 1003, ¶ 56; Ex. 1036, 6 (“URL” is “Acronym
`
`for Uniform Resource Locator. An address for a resource on the Internet.”). The
`
`’070 patent states that “URL” refers to a “unique resource locator,” but a POSA
`
`would recognize that it is the same thing as a typical URL, as it refers to the
`
`address entered into a web browser to be directed to the specified web page. See
`
`Ex. 1001, Fig. 3 (providing sample website address “http://cyph