Invendu publicitaire, also known as unsold advertising, refers to any type of promotional material or space that has not been purchased or utilized by a company or advertiser. This can include unused ad space in print publications, unsold commercial airtime on television or radio, or unfulfilled sponsorship agreements. Invendu publicitaire can occur for various reasons, such as a lack of interest from potential buyers, budget constraints, or changes in marketing strategies. It is often seen as a missed opportunity for businesses to reach their target audience and can result in financial losses for media outlets or event organizers.