Several Chipotle Mexican Grill (CMG) restaurants have pulled pork from their menus.

The reason behind Chipotle pulling pork from some of its restaurants has to do with one of its suppliers. The company discovered that the supplier didn’t meet its standards and cut them off. This resulted in a shortage of pork and the company having to stop selling it at some restaurants, reports CNN Money.

Chipotle hasn’t given the name of the pork supplier that didn’t meet its standards. It also hasn’t let its locations know when they will be getting new supplies of pork in. Niman Ranch

, a suppler of pork for the restaurant chain, has stated that it wasn’t the supplier that the company stopped ordering from, CNN Money notes.

The shortage of pork due to the lost supplier has caused Chipotle to have to pull the item from menus at roughly 600 of its locations.

CMG shares were down slightly as of Wednesday afternoon.

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