Patent assignee · US · COMPANY

DPHI Acquisitions, Inc.

111Patents
7Active
111Granted
38Portfolio score

Filing activity: Sep 10, 1999 → Jul 24, 2008 · 7 expiring within 5 years

Most-cited patents

PatentTitleAreaCited byStatus
US7110982B2 Secure access method and system Physics 94 Expired
US6636966B1 Digital rights management within an embedded storage device Physics 78 Expired
US6823398B1 File system management embedded in a storage device Emerging Cross-Sectional Technologies 73 Expired
US6980652B1 Combination mastered and writeable medium and use in electronic internet appliance Physics 42 Expired
US7191153B1 Content distribution method and apparatus Physics 36 Expired
US7549044B2 Block-level storage device with content security Electricity 35 Expired
US7196979B2 Calibration storage methods for a digital focus and tracking servo system with calibration Physics 32 Expired
US7310821B2 Host certification method and system Physics 31 Expired
US6631359B1 Writeable medium access control using a medium writeable area Physics 30 Expired
US6754151B2 BEMF timing system Physics 17 Expired
US7051054B1 Method and apparatus for emulating read/write file system on a write-once storage disk Emerging Cross-Sectional Technologies 15 Expired
US6809995B2 Digital focus and tracking servo system Physics 15 Expired
US6687215B1 Low profile and medium protecting cartridge assembly Physics 13 Expired
US7020054B2 Digital servo system with biased feed-forward Physics 13 Expired
US6970403B2 Calibration of tracking error signal offset in a tracking servo system Physics 12 Expired
US6781929B2 Digital tracking servo system with multi-track seek Physics 12 Expired
US6813226B2 Calibration of a focus sum threshold in a focus servo system Physics 11 Expired
US6906985B2 Calibration of tracking error signal gain in a tracking servo system Physics 11 Expired
US6965547B2 Tracking and focus servo system with error signal inverse non-linearity calibration Physics 11 Expired
US6914724B2 Micro lens and method and apparatus for fabricating Physics 10 Expired
US7092322B2 Calibration of focus error signal offset in a focus servo system Physics 10 Expired
US6632310B2 Disk drive actuator and method of making same Emerging Cross-Sectional Technologies 9 Expired
US6958957B2 Digital tracking and focus servo system with TES to FES crosstalk calibration Physics 9 Expired
US7023776B2 Calibration initiation methods for a tracking and focus servo system Physics 9 Expired
US6904007B2 Digital servo system with loop gain calibration Physics 8 Expired

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.