I'm sure they do but even more interesting is the patent our patents reference:

US Patent References

4685057
Memory mapping system
Issued on: August 4, 1987
Inventor: Lemone, et al. 5263160
Augmented doubly-linked list search and management method for a system having data stored in a list of data elements in memory
Issued on: November 16, 1993
Inventor: Porter, Jr., et al. 5337275
Method for releasing space in flash EEPROM memory array to allow the storage of compressed data
Issued on: August 9, 1994
Inventor: Garner 5341330
Method for writing to a flash memory array during erase suspend intervals
Issued on: August 23, 1994
Inventor: Wells, et al. 5357475
Method for detaching sectors in a flash EEPROM memory array
Issued on: October 18, 1994
Inventor: Hasbun, et al. 5404485
Flash file system
Issued on: April 4, 1995
Inventor: Ban 5437020
Method and circuitry for detecting lost sectors of data in a solid state memory disk
Issued on: July 25, 1995
Inventor: Wells, et al. 5448577
Method for reliably storing non-data fields in a flash EEPROM memory array
Issued on: September 5, 1995
Inventor: Wells, et al. 5454103
Method and apparatus for file storage allocation for secondary storage using large and small file blocks
Issued on: September 26, 1995
Inventor: Coverston, et al. 5551020
System for the compacting and logical linking of data blocks in files to optimize available physical storage
Issued on: August 27, 1996
Inventor: Flax, et al. 5581736
Method and system for dynamically sharing RAM between virtual memory and disk cache
Issued on: December 3, 1996
Inventor: Smith 5586291
Disk controller with volatile and non-volatile cache memories
Issued on: December 17, 1996
Inventor: Lasker, et al. 5602987
Flash EEprom system
Issued on: February 11, 1997
Inventor: Harari, et al.

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