PTO Manual of Classification for US patents

PTO Manual of Classification for US patents

What follows are the subclasses from one class of the Manual of Classification for US patents. As you scroll through the list and encounter a class/subclass of interest, you can jump back to the top and retrieve patent titles by entering the class/subclass in the box below.


Enter a class/subclass code here to get a list of patent titles. Use any of the following forms:
363-131 121-55A 14-.5
that is, no embedded spaces, class and subclass seperated by a dash, and any subclass letters capitalized. Currently Design Patent titles (those in the classes of the form Dxx.yy) are not retreivable.

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Class Number: 380
 Class Title: CRYPTOGRAPHY

Subclass  Subclass
Number    Title

  1       CRYPTANALYSIS
  2       EQUIPMENT TEST OR MALFUNCTION INDICATION
  3       STORED INFORMATION ACCESS OR COPY PREVENTION
  4       .Digital data (e.g., software program protection, data
            encryption)
  5       .Video
  6       ELECTRIC SIGNAL MASKING
  7       .Video
  8       .By signal having discrete step amplitude variation
  9       ELECTRIC SIGNAL MODIFICATION (E.G., SCRAMBLING)
  10      .Video
  11      ..Variable time delay modulation of baseband video signal
  12      ..Carrier phase shift
  13      ..Carrier frequency conversion
  14      ..Nonstandard scan of video information
  15      ..By modifying synchronizing signal
  16      ..Record or coin controlled
  17      ..Phase inversion of scan line information
  18      ..Facsimile
  19      ..Encrypting of accompanying audio signal
  20      ..Control coding
  21      .Having transmission or distribution of key signal
  22      .With magnetic record carrier (e.g., tape, drum)
  23      .With user or record actuated authentication
  24      ..Electronic funds transfer (e.g., automatic teller)
  25      ..Computer
  26      .With mechanical control of signal encryption (e.g., cam)
  27      ..By perforated record
  28      .By particular algorithmic function encoding
  29      ..NBS/DES algorithm
  30      ..Public key
  31      .Plural modulation of single carrier
  32      ..Wobbling of carrier
  33      .Using plural paths or channels
  34      ..Plural carrier frequencies
  35      .Variable time delay modulation
  36      .Time segment interchange
  37      ..Block/data stream enciphering
  38      .Frequency shift or inversion
  39      ..With plural band pass filters
  40      .With plural band pass filters
  41      .With quantizing and subsequent normalizing of signal (e.g.,
            reentry telephone circuitry)
  42      .Data stream/substitution enciphering
  43      ..Key sequence signal combined with data signal
  44      ..With particular key generator
  45      ...Multiple key level
  46      ...Nonlinear (e.g., pseudorandom)
  47      ...Plural generators
  48      .With particular synchronization or initiation
  49      .With digital signal handling (e.g., digital control, digital
            computer communication))
  50      ..Including shift register or memory
  51      .With production of printed copy (e.g., printer, typewriter)
  52      .Including particular structure or housing (e.g., display,
            keyboard)
  53      ..Audio transducer mounting or structure
  54      BY MODIFYING OPTICAL IMAGE (E.G., TRANSMISSIVE OVERLAY)
  55      WITH PRODUCTION OF PRINTED COPY (E.G., CRYPTOGRAPHIC PRINTER OR
           TYPEWRITER)
  56      SELECTIVELY MOVABLE ELEMENT HAVING CODE CHARACTERS
  57      .Rotatable
  58      ..Characters on peripheral surface (e.g., cylinder section)
  59      MISCELLANEOUS