A stream of studies investigates shareholder wealth effects of marketing investments into sport sponsorship properties. While research generally upholds a positive relationship between sponsorship agreements and shareholder wealth, the relationship remains unclear for several sponsorship categories. With more specific attention to research design issues, this paper replicates and extends prior research in two of these areas: official product and Olympic sponsorship announcements. This paper notes that inclusion of observations with potentially confounding events materially affects results reported by the original authors. The first study identifies a significant positive shareholder wealth effect associated with initial official product sponsorship announcement but not for renewal of such announcements. The second study resolves conflicting views from prior research regarding Olympic sponsorships. Although a negative overall relationship exists for sponsors of the 1996 Atlanta Olympics, the market's negative view of costly, top-tier global sponsorships largely drives this result. © 2012 Elsevier Inc.