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.
Magneto-optical drive
Magneto-optical drives are not Floptical drives, which likewise combine ferromagnetic and optical technologies, albeit in a different manner. Flopticals are 21 megabyte 3.5" magnetic diskettes using optical tracks to increase the tracking precision of the magnetic head, from the usual 135 tracks per inch to 1,250 tracks per inch. No laser or heating is involved; a simple infrared LED is used to follow the optical tracks, while a magnetic head touches the recording surface. The drives can also read and write traditional 3.5" diskettes, although not the 2.88 megabyte variety. Flopticals were manufactured by Insite Peripherals, a company founded by Jim Burke.