Yoshiro Nakamatsu
Nakamatsu claims IBM reached licensing agreements with him in the late 1970s. He also claims to have licensed his floppy disk to IBM in 1979, but that the details are "confidential". An IBM spokesman, Mac Jeffery, confirmed that the company did license some of his patents, but claimed they were not for the floppy disk, which he claimed IBM invented on its own. Another IBM spokesman, Brian Doyle, said they licensed 14 patents from Nakamatsu, but also claimed that they do not have anything to do with the floppy disk.
Macintosh 128K/512K technical details
The Macintosh's persistent storage medium was Sony's floppy diskette drive. This drive replaced the Apple ]['s Shugart drive, and later, the less reliable but more storage dense Apple 871K FileWare/"Twiggy" floppy drive used in the original Lisa, as the storage medium chosen to be implemented in the original Macintosh. The single-sided 3.5 inch floppy stored 400 KB by spinning the disk slower when the outer edge was used. A separate microcontroller, the IWM (Integrated Woz Machine), was dedicated to disk control. The floppy operated by polled I/O. Disk access was not seamless as in today's computers, and loading and saving files were operations that stopped the entire machine.