Signaling theory suggests that firms send signals to stakeholders to reduce information asymmetry. Research, however, has rarely examined how investors interpret signals that are equivocal. We suggest that sensemaking serves as an important process by which investors interpret firm signals, and salient contextual cues influence the sensemaking process. We examine an equivocal signal, the adoption of a poison pill, as a means of examining investor interpretation of the signal and the role of contextual cues in influencing interpretation. Using a sample of 578 poison pill adoptions and controlling for self-selection, we find that investors react negatively to poison pills adopted to protect net operating losses (NOL poison pills) but positively to poison pills adopted when the firm is in receipt of a takeover offer (in-play poison pills). Assessing the role of contextual cues, our results suggest that CEO duality, the proportion of inside directors on the firm’s board, the firm’s R&D investments, and industry concentration also condition investor response to specific-purpose poison pill adoption. Our study contributes to research on signaling theory, sensemaking, and corporate governance by examining how investors interpret a firm’s equivocal governance decisions.