The information intermediary role of short sellers

This paper examines the conditions under which the market responds to disclosures of significant increases in short selling, and whether proxies for earnings expectations and alternative information sources help explain this response. Our sample is based on firms that experience abnormal short interest increases ("short spikes") during 1989-1998. We find that the mean abnormal return around short spike announcements is significantly more negative for firms with low analyst following, consistent with short sellers providing perceived value when there are limited alternative sources of guidance available. For firms with high analyst following we find the market response is dependent on earnings levels, consistent with investors viewing a short interest increase as providing information about the sustainability of earnings. Additional analyses reveal that these inferences are not affected by measures of firms' earnings quality or by the relative size of the short spike. We infer from our analyses that the information content of short interest disclosures is conditional on both the firms' existing information environment and expectations of future performance as conveyed by prior earnings. This inference is consistent with short sellers' role as information intermediaries covering the lower tail of earnings expectations.