US 7203844

Here's a concise summary of US Patent 7203844:

US Patent 7203844: Method and system for a recursive security protocol for digital copyright control

• Title: Method and system for a recursive security protocol for digital copyright control
• Inventor: William V. Oxford
• Current Assignee: Torus Ventures LLC
• Filing Date: 2003-06-19
• Issue Date: 2007-04-10
• Abstract: Systems and methods are disclosed for security protocols that utilize various encryption techniques to protect digital content. These methods enable encoding any bit stream (e.g., audio/video, software) such that a user can make multiple backup copies, but still requires permission from copyright holders to use them. Embodiments involve encrypting a bit stream, associating it with a decryption algorithm, then encrypting that combination again, and so on, creating multiple layers of encryption. Decryption involves sequentially using associated algorithms and keys. Keys may reside on a server, in hardware on the target machine, or within key data structures, potentially managed by a central server. Message digests are used to verify the authenticity of encrypted or decrypted bit streams.

Plain-Language Overview of Independent Claims:

• Claim 1 (Method): This claim describes a multi-layered encryption process. It involves taking an initial digital content (a first bit stream), encrypting it, and linking the encrypted result with a first decryption method. Then, this combination (the first encrypted bit stream and its decryption method) is encrypted again, yielding a second encrypted package and a second decryption method. This second package is given to a user. To access the content, the user first decrypts the second package using the second decryption method and a second key to reveal the first encrypted content and its method. Finally, the user decrypts the first encrypted content using the first decryption method and a first key to obtain the original digital content.

• Claim 7 (System): This claim describes a system that performs the multi-layered encryption method of Claim 1. It specifies hardware or software "means" (modules) for each step: encrypting the first bit stream, associating it with a first decryption algorithm, encrypting the combined first encrypted bit stream and algorithm, associating that result with a second decryption algorithm, providing the second encrypted package to a recipient, receiving a request for access, decrypting the second package with a second key, and finally decrypting the first package with a first key to retrieve the original bit stream.

• Claim 14 (Method): This claim presents another multi-layered protection method. It involves encrypting a bit stream, associating it with a decryption algorithm, and then combining these two into a "data structure." This data structure is then encrypted and linked with a second decryption algorithm. This doubly encrypted structure and the second decryption algorithm are provided to a recipient. To use the content, the second decryption algorithm is used to decrypt the data structure, and then the first decryption algorithm is used to decrypt the original bit stream.

• Claim 20 (System): This claim describes a system designed to execute the method outlined in Claim 14. It includes various modules: an encryption module for the bit stream, a first association module for linking the encrypted stream with a decryption algorithm, a combination module to form a data structure, a second encryption module for the data structure, a second association module for linking the encrypted data structure with a second decryption algorithm, a provision module to send these to a recipient, and a decryption module to perform the two-step decryption process.

USPTO Database Search:
A search of the USPTO database for patent number 7203844 confirms the details above. The patent was granted on April 10, 2007, from application number 10/465,274 filed on June 19, 2003. Its legal status is "Expired - Lifetime", with an adjusted expiration date of 2025-08-09.

CAFC 2026 Dockets Search:
A review of the litigation data associated with US7203844 shows numerous cases filed in various District Courts, primarily in Texas (Eastern, Western, Northern, Southern Districts) and Delaware, extending through 2024 and into 2025. However, there are no specific entries for the Court of Appeals for the Federal Circuit (CAFC) dockets in 2026 directly linked to patent 7203844 in the provided Google Patents legal status information.