Famous Patents
William F. Semple, a dentist, was awarded the first US Patent on chewing gum in 1869. His recipe contained powdered chalk.
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 6690795 | Multiple keys for decrypting data in restricted-access television system An encryption system for restricted-access television systems. Multiple decryption keys are used to decrypt encrypted material which is transmitted to customers of a restricted-access television system.... | 02/10/2004 |
| 6088452 | Encoding technique for software and hardware An encoding technique of the invention protects software programs and hardware designs from being copied, tampered with, and its functions from being exposed. The software programs and hardware designs (collectively called programs) thus encoded still rem... | 07/11/2000 |
| 5923759 | System for securely exchanging data with smart cards A card-enabled processing system comprises a security module for securely exchanging data with cards, such as smart cards, and an application module for processing data from the smart cards. The security module encrypts and decrypts data using keys, which... | 07/13/1999 |
| 5917910 | Encrypting method and apparatus, recording method, decrypting method and apparatus, and recording medium When information to be recorded is encrypted by using an encryption key, an encryption key based on inherent information inherent in a recording medium is generated. The information to be recorded on the recording medium is encrypted based on the encrypti... | 06/29/1999 |
| 5915017 | Method and apparatus for securing programming data of programmable logic device An SRAM-based programmable logic device having decompression and decryption circuits between its EPROM nonvolatile programming data storage and its SRAM programming registers is secured against copying of the programming data because a would-be copyist wo... | 06/22/1999 |
| 5912969 | Information receiving and recording/reproducing apparatus/method having function for limiting/delimiting for protecting copyright of recording information An apparatus comprising a transmission system for transmitting an information signal, and a reception system including an information receiving unit for receiving the information signal, and an information recording/reproducing unit for recording/reproduc... | 06/15/1999 |
| 5907617 | Try before you buy software distribution and marketing system A computer-based system is provided for demonstrating software programs to a potential purchaser and for gathering marketing information related to the demonstration of the programs. The system enables the software programs for execution upon selection by... | 05/25/1999 |
| 5907621 | System and method for session management Apparatus and method is disclosed for providing user session continuity over several transactions being conducted on the internet. A secure token is made part of each HTML page sent to a user from the server computer and the token is returned to the serve... | 05/25/1999 |
| 5903647 | Self-launching encrypted digital information distribution system A computer-based self-launching system associated with a software program or other digital information is provided for distributing the software program or other digital information to a potential purchaser. The self-launching system is attached to a soft... | 05/11/1999 |
| 5903652 | System and apparatus for monitoring secure information in a computer network A secure transaction system apparatus and method provide for the auditing of secure messages in a computer network. The secure transaction system includes an electronic commerce service which is in communication with multiple consumer computers and multip... | 05/11/1999 |
| 5901224 | Quasi-reprographics with variable embedded data with applications to copyright management, and distribution control A method and apparatus for quasi-reprographically replicating a source document. The source document is digitized, appropriate locations for embedded code are detected, and any embedded code located in the digitized document along with the detected locati... | 05/04/1999 |
| 5900927 | Variable target autofocusing and range finder for measuring distance to a subject An image pickup frame is divided into a plurality of areas. A contrast at each area is measured. An area where a main subject is located is detected by comparing contrasts at areas. A distance to a subject in the area where the main subject is located is ... | 05/04/1999 |
| 5892827 | Method and apparatus for generating personal identification numbers for use in consumer transactions A system for generating authorization codes, such as personal identification numbers, at the point of distribution of certificates of value on which the authorization codes are to be printed or otherwise encoded. Because the authorization codes are genera... | 04/06/1999 |
| 5892826 | Data processor with flexible data encryption A data processor (20) which flexibly encrypts data within different address ranges includes an encryption determination circuit (50) to monitor an address conducted on an internal address bus (22) and when the address is within certain predefined ranges, ... | 04/06/1999 |
| 5889860 | Encryption system with transaction coded decryption key The encryption secured computer system (10) includes a server (12) that communicates with clients (14-20) across a public network (21) using a novel transaction coded decryption key technology that discourages wrongful redistribution of protected informat... | 03/30/1999 |
| 5887060 | Central database system for automatic software program sales A computer-based system is provided for automatic sales of software programs. The system accesses a software program within a computer database and maintains the software program in a locked state in order to prevent unauthorized duplication of the softwa... | 03/23/1999 |
| 5884026 | Personal computer having a security function, a method of implementing the security function, and methods of installing and detaching a security device to/from a computer A personal computer having a security function, a security method therefor, and methods of installing and detaching a security device are provided. In the security method, a password is dispersedly stored in the personal computer and a hard disk is booted... | 03/16/1999 |
| 5883954 | Self-launching encrypted try before you buy software distribution system A computer-based self-launching system associated with a software program is provided for demonstrating the software program to a potential purchaser of the program. The self-launching system is attached to a software program and includes the ability to l... | 03/16/1999 |
| 5883955 | On-line try before you buy software distribution system A computer-based on-line system is provided for demonstrating software programs to a potential purchaser. The system receives from an on-line system a software program to be demonstrated, and maintains the software program in a locked state in order to pr... | 03/16/1999 |
| 5881154 | Data scramble transmission system A data scramble transmission system with a data transmission link coupled between sending and receiving ends is provided. The link adopts transmission frames each of which is constituted by data and control bits periodically added to the data. The system ... | 03/09/1999 |
| 5878137 | Method for obtaining authenticity identification devices for using services in general, and device obtained thereby Method for obtaining authenticity identification devices for using services in general wherein authenticity is guaranteed without resorting to the manufacturer of the device to ensure its validity; the method has the particularity that it consists in prep... | 03/02/1999 |
| 5878134 | Secure access systems utilizing more than one IC card A secure access system for controlling access to a plurality of items. The system includes a first IC card reader adapted to receive a first IC card which includes first control information, a second IC card reader adapted to receive a second IC card whic... | 03/02/1999 |
| 5872848 | Method and apparatus for witnessed authentication of electronic documents The present invention consists of a method and apparatus for authenticating an electronic document. In one embodiment of the invention, a party wishing to digitally sign an electronic document (the "client") stores the unsigned electronic document, and th... | 02/16/1999 |
| 5870475 | Facilitating secure communications in a distribution network In a hybrid fiber-coax distribution network, communications between a central station and particular end stations are encrypted using a working key (WK) of a symmetric encryption scheme. The central station has a public and private key (PPK) of a PPK encr... | 02/09/1999 |
| 5857025 | Electronic encryption device and method A device and method is provided using a split processor based architecture to provide physical security of critical information by implementing a required protocol before releasing critical information. The critical information is used as a key to a crypt... | 01/05/1999 |
| 5857023 | Space efficient method of redeeming electronic payments A method of redeeming for a seller electronic payments generated by and received from a customer using a master key unknown to the seller. In anticipation of making electronic payments, a customer sends a bank the master key that he will use to generate e... | 01/05/1999 |
| 5841871 | Method for authenticating a user working in a distributed environment in the client/server mode A method for authenticating a user working in a distributed environment in the client/server mode, wherein each authentication is performed from a single piece of authentication information, known as the "passphrase", having a predetermined length and dur... | 11/24/1998 |
| 5841873 | Methods of detecting decryption errors In a data communications system, including an infrastructure arranged to communicate over a data channel with a plurality of data terminals, a method of detecting data decryption errors in a data packet includes receiving an encrypted data packet (213); d... | 11/24/1998 |
| 5838795 | Method and apparatus for statistical diffusion in iterated block substitution A method and apparatus for inter-round mixing in iterated block substitution systems is disclosed. The method involves optimizing inter-round mixing so that each sub-block of data affects each other in the same way. This is accomplished by applying a quic... | 11/17/1998 |
| 5838796 | Statistically optimized bit permutations in interated block substitution systems A method and apparatus for inter-round mixing in iterated block substitution systems is disclosed. The method involves optimizing inter-round mixing so that each data bit affects each other data bit in the same way. This is accomplished by applying a quic... | 11/17/1998 |
| 5838794 | Method and apparatus for inter-round mixing in iterated block substitution systems A method and apparatus for inter-round mixing in iterated block substitution systems is disclosed. The method involves optimizing inter-round mixing so that each sub-block of data affects each other in the same way. This is accomplished by applying a quic... | 11/17/1998 |
| 5835601 | File editing system and shared file editing system with file content secrecy, file version management, and asynchronous editing A file editing system that provides a high file content secrecy, a file version management, and an asynchronous editing is disclosed. For a high file content secrecy, the block data of files managed by a file management server device are enciphered in uni... | 11/10/1998 |
| 5835600 | Block encryption algorithm with data-dependent rotations A simple encryption and decryption device has been developed. The underlying algorithm is a fast block cipher that may be implemented efficiently in hardware or software. The algorithm makes heavy use of data-dependent rotations. The amount of each rotati... | 11/10/1998 |
| 5831717 | Obstacle detecting apparatus which employs a laser An obstacle detecting apparatus for ensuring that the transmitted light power is sufficient to detect an obstacle at a long distance, but yet not be harmful to human eyes. The apparatus comprises a light transmitting device for transmitting a pulsed light... | 11/03/1998 |
| 5832089 | Off-line compatible electronic cash method and system An off-line electronic cash system having an electronic coin, a bank B, a payee S, and a user U with an account at the bank B as well as a user password zu,i, has a method for performing an electronic cash transfer. An electronic coin is withdr... | 11/03/1998 |
| 5828752 | Pseudo-random number generator and communication system employing the same A communication apparatus through which encryption/decryption processing can be executed at high speed includes a CPU for performing overall control of the apparatus, an encryption unit for encrypting communication data that has been stored in a RAM and o... | 10/27/1998 |
| 5825875 | Process for loading a protected storage zone of an information processing device, and associated device The invention relates to a process for loading a protected storage zone of an information processing device, with confidential data and/or programs, and to the associated information processing device. The information processing device (1) includes a module (8... | 10/20/1998 |
| 5825879 | System and method for copy-protecting distributed video content A secure video content processor ("SVCP") which receives encrypted digital video information and converts it into analog information for a monitor while preventing unauthorized access to the intermediate unencrypted digital data. The SVCP uses hardware en... | 10/20/1998 |
| 5825887 | Transmitting and receiving apparatus for full code correlation operation under encryption for satellite positioning system The transmitting and receiving apparatus and method for full code correlation operation under encryption for the Satellite Positioning System (SATPS) are disclosed. The apparatus includes a central station designed to receive SATPS satellites encoded info... | 10/20/1998 |
| 5825892 | Protecting images with an image watermark A robust means of watermarking a digitized image with a highly random sequence of pixel brightness multipliers is presented. The random sequence is formed from `robust-watermarking-parameters` selected and known only by the marker and/or the marking entit... | 10/20/1998 |
