When a single product is associated with multiple offers (for example, the same pair of shoes is offered by different merchants), then AggregateOffer can be used. Note: AggregateOffers are normally expected to associate multiple offers that all share the same defined businessFunction value, or default to http://purl.org/goodrelations/v1#Sell if businessFunction is not explicitly defined.
When a single product is associated with multiple offers (for example, the same pair of shoes is offered by different merchants), then AggregateOffer can be used.