The InventoryMaxQuantity can limit the inventory available for Amazon so that it will never show the full quantity on Amazon even if there really is more available. For example, if there are 500 units available for a specific product and the InventoryMaxQuantity is set to 10, a quantity of 10 will be sent to Amazon. But if the available quantity drops to 5, a quantity of 5 will be sent to Amazon.
InventoryMaxQuantity can be set on a company level and on a product level on AmazonProperties. Before it can be set on a specific product, it first needs to be enabled on the company level. For example, when enabled on a company level with InventoryMaxQuantity set to 10, all products will default to 10. By overriding the InventoryMaxQuantity on a product level, a quantity of 5 of that product will be sent to Amazon while a quantity of 10 will sent for all other products.