Final answer:
A purchase order is not automatically legally binding upon issuance; it typically becomes a binding contract when the seller accepts it. The legal status also depends on terms, the relationship between parties, industry regulations, and legal capacity.
Step-by-step explanation:
Whether a purchase order is legally binding once issued by the buyer depends on a few factors. Generally, a purchase order by itself might not be legally binding until the seller accepts it. Acceptance can be through an acknowledgment, such as a confirmation of the order, delivery of the goods, or another method that clearly shows the seller intends to fulfill the order. The contract is typically formed when the seller accepts the terms presented in the purchase order, not merely upon the issuance of the purchase order by the buyer.
However, the legal binding nature of a purchase order can also depend on the existing relationship between the parties, any specific terms and conditions that were included in the purchase order, and the regulatory conditions of the particular industry or location. Additionally, both parties need to have the capacity to enter into the contract, and the contract must not involve any illegal activities. Therefore, the correct answer to the question is that it depends.