Online video advertising (OVAs) has emerged as a strong medium for advertisers to market and share information about their products and services. Despite its significance, few studies had delved into the mechanisms that propel consumers to partake in the viral video phenomena. Therefore, the current study explore factors that drive OVAs sharing behaviours among the group that do it the most; the Millennial Generation. This exploratory study utilized a series of focus groups to provide empirical evidence that can explain both internal and external influences for this phenomenon. Key findings indicate that key elements of OVAs sharing behaviour are; (1) internal factors that include specific antecedents towards the Theory of Planned Behaviour; (2) external factors concerning the organization; and (3) the effects of intrusion perception during the consumption process. The study then proposes a comprehensive model that may help marketers to strategize their OVA efforts.