Who Western Digital buys from and sells to
Makes hard disk drives, mostly high-capacity nearline drives bought by cloud data centres.
Buys from 3
- HoyaHOCPYglass substrates for platters
- NidecNJDCYspindle motors
- Resonacrecording media
Sells to 3
- Hyperscalersnearline HDDs for cloud storagethree customers 16%, 15% and 13% of FY2026 revenue (10-K)
- MicrosoftMSFTexabytes for Azure storage
- AmazonAMZNexabytes for AWS storage
Where the chain could break
- Top ten customers were 73% of FY2026 revenue; three were 44%
- Three HDD makers left; head and media output concentrated in Thailand, Malaysia, the Philippines
Competes with
- SeagateSTXnearline drives sold to the same clouds
- Toshibathe third HDD maker
Mapped by hand from filings and company reporting, as of October 2026. It shows the relationships that matter most, not every contract: most are never disclosed, and agreements change.