This study uses the Paris Agreement as a proxy for global environmental awareness to examine its impact on US firms’ attention to climate risk, particularly when facing potential pressure from corporate customers in high-carbon-emission industries. We measure firms’ attention to climate risk through the degree of climate-related content in U.S. suppliers’ M&A deal announcements captured in their press releases. Using a difference-in-difference analysis, we find that, following the Paris Agreement, acquirers with high-emission customers experience a significantly greater increase in climate risk considerations, but not innovation, in their M&A deals compared to those with low-emission customers. Additionally, M&As with higher degrees of climate risk are associated with worse post-merger operating performance for acquirers with high-emission customers than those with low-carbon emission customers. By engaging in M&As dealing with higher climate risk, firms with high-carbon-emission customers can demonstrate their efforts to reduce climate risk to customers, which shows positive investor reactions and long-term value creation compared to counterparties.