> Quantum [...] were beating IBM and IBM needed more capacity so IBM bought them.
No, Maxtor bought Quantum's HDD business, and Seagate later bought Maxtor [1], [2], [3].
> Western Digital who sold the drive business to Toshiba
No, WDC sold some assets related to desktop (not server) 3.5" (not 2.5") HDDs to Toshiba [4], [5], [6].
[1] https://en.wikipedia.org/wiki/Maxtor#Acquisition_of_the_Quan...
[2] http://www.cnet.com/news/maxtor-buys-rival-quantum-to-become...
[3] http://www.pcmag.com/article2/0,2817,1966943,00.asp
[4] https://en.wikipedia.org/wiki/HGST#History
[5] http://techreport.com/news/22553/toshiba-becomes-third-playe...
[6] https://news.ycombinator.com/item?id=8367993
> Quantum [...] were beating IBM and IBM needed more capacity so IBM bought them.
No, Maxtor bought Quantum's HDD business, and Seagate later bought Maxtor [1], [2], [3].
> Western Digital who sold the drive business to Toshiba
No, WDC sold some assets related to desktop (not server) 3.5" (not 2.5") HDDs to Toshiba [4], [5], [6].
[1] https://en.wikipedia.org/wiki/Maxtor#Acquisition_of_the_Quan...
[2] http://www.cnet.com/news/maxtor-buys-rival-quantum-to-become...
[3] http://www.pcmag.com/article2/0,2817,1966943,00.asp
[4] https://en.wikipedia.org/wiki/HGST#History
[5] http://techreport.com/news/22553/toshiba-becomes-third-playe...
[6] https://news.ycombinator.com/item?id=8367993