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# Friedman Documents

HomeHelpful LinksNSA FOIADeclassification & Transparency InitiativesHistorical ReleasesFriedman-DocumentsPatent-Equipment

## Patent and Equipment Records

   (Folder ID: ACC17260) Application for Patent on Facsimile Enciphering System and Related Correspondence, 1943-1951 

   (Folder ID: ACC17261) Application for Patent on System for Enciphering Facsimiles and Related Correspondence, 1937-1959 

   (Folder ID: ACC17264) Application for Patent on Electrical Cryptograph and Related Correspondence, 1944-1959 

   (Folder ID: ACC17265) Application for Patent on Authenticating Device and Related Correspondence, 1944-1950 

   (Folder ID: ACC34839) Memoranda, Patent Applications Nos. 107,244 and 682,096 of William F. Friedman Re: Proposed Motion Control Means, 19 September 1949 

   (Folder ID: ACC34876) Memoranda on Cryptographic Patents and Friedman's Original Worksheets of the Hebern Solution, 1935-1948 

   (Folder ID: FOLDER 054) Guidelines for Security Classification, 1955; Open Source Mention of Use of Electronic Computers In Cryptography, 1957; Crypto-Mathematics Institute Bulletin, September 1958 

   (Folder ID: FOLDER 066) Patent Data SISDE-17, Application No. 478,193, 1936-1951 

   (Folder ID: FOLDER 067) Patent Data SISDE-18, Application No. 478,868, System for Enciphering and Deciphering Telephotograms, Friedman and Mauborgne (1943), 1924-1947 

   (Folder ID: FOLDER 068) Patent Data SISDE-14, Systems and Means for Enciphering and Deciphering Magnetically Recorded Signals, 1932-1937 

   (Folder ID: FOLDER 069) Patent Data SISDE-12 & SISDE-13, Cryptanalytic Coincidence Counter Ideomorph and Isomorph Locator, 1937-1950 

   (Folder ID: FOLDER 070) Patent Data SISDE-4, Serial No. 350,713, Patent No. 1,857,374, Cryptograph, Evans, Friedman, and Graham (1924), 1923-1924 

   (Folder ID: FOLDER 071) Extracted Minutes of Signal Corps Patent Board, Meetings No. 1-39 Regarding Crypto-Systems Discussions, 1936-1941 

   (Folder ID: FOLDER 072) Memoranda, Patent Publications, Issued Patents by Friedman, 1938-1955 

   (Folder ID: FOLDER 073) Correspondence, Historical Reports, Related to Patent Application 443,320, 1949-1951 

   (Folder ID: FOLDER 074) Memoranda, Policies, Patent Publications, Related to US Government Policy on Patents and Release of Technical Information by Government Employees, 1936-1951 (2 Folders) 

   (Folder ID: FOLDER 076) List of Pending Patent Applications AS of 1936 and Issued Patents 1926-1946 Showing Patent Number, Date Issued, Inventor(s), Title, and Description, 1946 

   (Folder ID: FOLDER 078) Randomizer Patent Papers SISDE-23, Serial No. 36,868, US Patent No. 2,166,137, Electric Switching Mechanism, Friedman and Rowlett (18 July 1939), 1926-1939 

   (Folder ID: FOLDER 079) Signal Intelligence Service (SIS) Systems, Randomizing Device for Electric Card Sorter, SISDE-23, Serial No. 36,868, US Patent No. 2,166,137, Friedman and Rowlett (18 July 1939), 1935-1939 

   (Folder ID: FOLDER 080) Correspondence, License, Patent Records, Notes, Diagrams, SISDE-25 Authentication System for Banks, 1944-1950 

   (Folder ID: FOLDER 081) Diagram, SISDE-26, Cryptographic Machine, 1927 

   (Folder ID: FOLDER 082) Correspondence, Description and Diagram, SISDE-30 Authentication Device, Rosen and Friedman, 1941 

   (Folder ID: FOLDER 083) List of SISDE Numbers for Cipher Devices, Machines, Etc. Including Type Number, Description, Inventor, US Patent Application Serial No., Date, US Patent No., and Date of Issue, 1942 

   (Folder ID: FOLDER 084) Memoranda, License, Descriptions, Diagrams, M-138 Patent Application, SISDE 15 & 16, Application No. 300,212, US Patent No. 2,395,863, Issued 5 March 1946, 1929-1946 

   (Folder ID: FOLDER 085) Correspondence, Description, Diagrams, SISDE-20, Cipher System and Apparatus for Plural-Unit-Code Telegraph Printer, 1936-1939 

   (Folder ID: FOLDER 086) Description, Notes, and Diagram for Invention of Simple Printing Mechanism for Baudot Code System, SISDE-22, 1935 

   (Folder ID: FOLDER 087) Working Notes and Diagrams for Invention of Means for Controlling Displacements of Cipher Wheels, Hebern Type of Cryptograph, SISDE-21, 27 March 1935 

   (Folder ID: FOLDER 088) Correspondence, Description, Diagrams, SIS Systems SISDE-11-Cipher Wheel Commuters, Internally Controlled, Serial No. 70,412, Formerly Known AS M-161, 1935-1947 

   (Folder ID: FOLDER 089) Notes and Diagrams, Subjects Include Printing Telegraphy, Protecting Crytpoteleprinter Transmissions, Electric Cryptograph, Special Modifications In M-161 for A Smaller Cryptograph, 1935-1943 

   (Folder ID: FOLDER 092) Diagram, Means and Methods of Controlling Intermittent Action of the Second of Two Key-Tape Transmitters, At&t System, SISDE-19, 26 March 1935 

   (Folder ID: FOLDER 096) US and UK Patent Publications, 1912-1936 

   (Folder ID: FOLDER 097) Diagrams, Descriptions, Patent Application Files, SISDE-29, Converter M228, Serial No. 443,320, Crypt System and Apparatus for Electrical Printing Telegraphy (16 May 1942), 1941-1953 

   (Folder ID: FOLDER 098) Diagrams, Descriptions, Patent Application Files, SISDE-24 Stylus Operated Keyboard for A Small Portable Cryptograph (Converter M-325), 1944-1953 

   (Folder ID: FOLDER 099) Photographs, Drawings, and Photostated Pictures of the M-325, 1935 

   (Folder ID: FOLDER 100) Correspondence, Contract, Contract Bids, Photographs, and Diagrams, Supply and Installation of A Complete Electric Burglar Alarm System In Army Munitions Building, Washington, D.C., 1940 

   (Folder ID: FOLDER 101) Volume I General Description Report (Including Photographs and Diagrams) on "DERVISH (Building Block Philosophy of Analytic Machine Assembly with Rotor Solution Devices) Given to Friedman, Memo on Friedman's Analysis of DERVISH, 1954 

   (Folder ID: FOLDER 102) War Department Publication, Technical Paper of the Signal Intelligence Section War Plans and Training Division (Register No. 11), Analysis of A Mechanico-Electrical Cryptograph Part 11, 1935 

   (Folder ID: FOLDER 103) Memoranda, Drawings, and Cryptograph Specifications Description, SISDE-6 SIS (Signal Intelligence Service) System-Message Authentication, 1933-1935 

   (Folder ID: FOLDER 111) Patent File, Navy Electric Ciphering Machines (ECM), 1924-1945 

   (Folder ID: FOLDER 114) Memoranda, Electronic Code Machine (ECM) Hebern (Including Negative Images of the Machine), 1924 

   (Folder ID: FOLDER 115) Memoranda and Working Notes, List of Patents on Electro-Mechanical Cipher Machines Pertinent to the Hebern Case, 1949 

   (Folder ID: FOLDER 116) Memoranda, Litigation Files, Patent Files, Diagrams, Newspaper Clippings, Relating to the Hebern Patent Infringement Claim, 1922-1949 

   (Folder ID: FOLDER 118) Instruction Book for Converter M-134-T2 and Associated Electrical Typewriter (Including Photographs and Diagrams), 1936 

   (Folder ID: FOLDER 119) Friedman's Patent File (Including Photographs and Diagrams) on Converter M-134-T2, US Patent Serial No. 682,096, SISDE-7, 1933-1952 

   (Folder ID: FOLDER 120) Memoranda and Reports Related to Policies on the Use of SIGABA/ECM (Electric Ciphering Machines), 1940-1952 

   (Folder ID: FOLDER 121) Memoranda and Reports Related to Policies on the Use of SIGABA/ECM (Electric Ciphering Machines), 1943-1950 

   (Folder ID: FOLDER 122) Memoranda and Reports Related to Policies on the Use of SIGABA/ECM (Electric Ciphering Machines), Includes Photographs and Diagrams, 1948-1952 

   (Folder ID: FOLDER 123) History of the M-134-C, Three Volumes, 1944-1952 (2 Folders) 

   (Folder ID: FOLDER 126) Signal Corps Laboratories, Description and Operating Instructions for Converter M-134 (Including Photographs and Diagram), 1932 

   (Folder ID: FOLDER 127) SIGABA SISDE-28, Method of Commutator Control for M-134-T2, Friedman and Graham, 1933-1941 

   (Folder ID: FOLDER 128) Patent File, SISDE-5, Single Commutator Cryptograph, Serial No. 588,344, Patent No. 2,028,772, Friedman and Graham, 1930-1936 

   (Folder ID: FOLDER 129) Patent File, SIGABA SISDE-8, Modified M-134-T2, Serial No. 107,244, Means for Controlling Displacement of Cipher Wheels on Hebern Type Cryptograph, 1935-1955 

   (Folder ID: FOLDER 130) Patent File, SIGABA Signals Intelligence Service (SIS) Systems, M-134-T2 (SISDE-7), Serial No. 682,096, 1933-1941 

   (Folder ID: FOLDER 131) Patent File, SISDE-11 Friedman and Rowlett Self-Controlled Cryptographs, Serial No. 70,412, 1935-1953 

   (Folder ID: FOLDER 132) Patent File, SISDE-10, File on Patent Application for Cipher Machine, Constantly Rotating Commutator Machine, Serial No. 157,383, 1936-1938 

   (Folder ID: FOLDER 133) Patent File, SISDE-6 Authentograph System, 1935-1937 

   (Folder ID: FOLDER 137) Patent File, SISDE-31 Indicating Device, 1936 

   (Folder ID: FOLDER 143) NSA Field Commanders Conference Book, March 1955; Official Report of the NSA Field Commanders Conference, April 1955 

   (Folder ID: FOLDER 371) Memoranda and Correspondence, Surplus Disposal and Exchange of Cryptographic Equipment (M-209), 1936-1954 

   (Folder ID: FOLDER 372) Memoranda, Release of Crypto Equipment to Foreign Governments (M-209), 1953-1954 

   (Folder ID: FOLDER 397) Hagelin Telecrypto System, 1950-1952 

   (Folder ID: FOLDER 398) Hagelin Patents, 1942-1954 

   (Folder ID: FOLDER 399) Correspondence on Inventions, Patents, and Unsolicited Suggestions, 1932-1953 

   (Folder ID: FOLDER 400) Communications Security and the Purchase of Hagelin Machines, 1952 

   (Folder ID: FOLDER 425) Reports, US/UK Communications Security (COMSEC) Equipment, 1953 

   (Folder ID: FOLDER 443) Papers on the Security of AFSAM 4a Machine (1955), Plain Text Radiation Study of Tsec/Kl-7, Comments on Afsay D802 (1955 "Enciphered Motion" Branching Structure, 1955 

   (Folder ID: FOLDER 444) Report, Pneumatic Authenticator or DEM 498, 1954 

   (Folder ID: FOLDER 473) Memoranda and Reports Related to the Development, Maintenance, and Service Tests of Cryptographic Equipment, 1946-1949 

   (Folder ID: FOLDER 476) Extracted Correspondence Related to Patent Information Related to Theodore I. Przysiecki and Dehn (US Patent Nos. 2,405,570 and 2,401,507), 1947-1948 

   (Folder ID: FOLDER 482) Storage and Destruction of SIGSALY and Associated Equipments, 1947-1948 

   (Folder ID: FOLDER 483) Memoranda and Reports, Use of SIGABA In Conjunction with Standard IBM Codatype Units, 1943 

   (Folder ID: FOLDER 484) Status Reports of Research and Development Phases of Cryptographic Equipment, Extract from the Final Report of G-2-D, General Headquarters (Ghq) American Expeditionary Forces (Aef (1 May 1919) Regarding Censorship and Use of Invisible Ink, 1944-1946 

   (Folder ID: FOLDER 485) Memoranda, Procedures, Policies, and Requirements Related to Packaging and Long-Term Storage of Various Cryptographic Devices, 1944-1949 

   (Folder ID: FOLDER 498) Photographs and Negatives, Enigma Printing Model and Non-Printing Model (R-27), 1954 

   (Folder ID: FOLDER 501) SISDE-11 Drawings, 1931-1935 

   (Folder ID: FOLDER 514) Description of the General Principles of an Invention of A Machine for Locating Idiomorphs and Isomorphs In Cryptanalysis, 1937-1938 

   (Folder ID: FOLDER 515) Memoranda and Reports on the Wadsworth, Decius, Cipher Device, 1943-1949 

   (Folder ID: FOLDER 519) Memoranda Regarding Modification and Instruction Manual of the M-209, 1947-1949 

   (Folder ID: FOLDER 520) Enigma Materials for Hand Method Attack with Paper Cipher Strips by Colonel Friedman, Arlington School, 1943-1945 

   (Folder ID: FOLDER 521) Memoranda Regarding Suggested Solution of Commercial Enigma, 1943 

   (Folder ID: FOLDER 527) Memoranda and Reports on Legislation and Patents Compiled by Friedman, 1937-1948 

   (Folder ID: FOLDER 539) Communications and Cryptographic Equipment Research, 1934-1951 

   (Folder ID: FOLDER 540) Communication and Cryptographic Equipment Research, Etx Telewriter, 1949-1951 

   (Folder ID: FOLDER 542) Memoranda Regarding Authenticating Device, 1935-1944 

   (Folder ID: FOLDER 543) Memoranda and Reports Regarding A Cipher Teleprinter, 1947-1950 

Folder ID: (FOLDER 544) - Folder not releasable

   (Folder ID: FOLDER 545) Correspondence on Printer Telegraph Cipher Machines, 1919-1935 

   (Folder ID: FOLDER 546) Correspondence on Printer Telegraph Cipher Machines, 1921 

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##### NSA.GOV

                                - About
                                - Leadership
                                - Cybersecurity Collaboration Center 
                                - National Cryptologic Museum 
                                - Contact NSA 
                                - Accessibility
                                - ABA Notice
                                - Site Policies

##### CULTURE

                                - Core Values
                                - Operating Authorities
                                -  Civil Liberties, Privacy, & Transparency Office 
                                - Compliance
                                - Diversity, Equity, Inclusion, & Accessibility
                                - General Counsel
                                - NSA Inspector General

##### HELPFUL LINKS

                                -  
                                - NSA Freedom of Information Act
                                - Privacy Act Requests
                                - Request a Speaker
                                - Prepublication Review
                                - Media Inquiry
                                - Frequently Asked Questions

##### RESOURCES

                                - Classified Materiel Conversion
                                - Commercial Solutions for Classified Program (CSfC) ​
                                - Cryptographic Support Services 
                                - Media Destruction Guidance 
                                - NSA Open Source

##### RELATED LINKS

                                - DNI.gov
                                - Defense.gov
                                - IC on the Record
                                - Intelligence.gov

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