This pops up in low latency HFT specifically with networking cards. Certain network cards have either a bug or combination of features that work in an interest

This pops up in low latency HFT specifically with networking cards. Certain network cards have either a bug or combination of features that work in an interesting way to the benefit of the trading firm. These bugs (and features too) sometimes get removed in favor of either getting rid of the bug or those features are seen as not needed for the larger market etc. Therefore, firms will sometimes attempt to buy up all available supply of certain models.