<p>The U.S. Securities and Exchange Commission (SEC) mandates disclosure of Article 11 pro forma financial statements (pro formas) for acquisitions that exceed one of three bright-line materiality thresholds. Motivated by two theories of mandated disclosure, I investigate the conditions under which mandated pro forma disclosure improves forecast accuracy and mitigates incentive alignment problems. My findings indicate that pro formas reduce post-acquisition forecast errors when there is a weak pre-acquisition information environment. The reduction in forecast errors is larger when pro formas contain more income statement disaggregation and footnote disclosure. Using announcement returns, deal failure, and future profitability to measure acquisition quality, I find that pro formas mitigate an incentive alignment problem by increasing transparency. The forecasting and incentive alignment benefits concentrate in the same subsamples, suggesting that pro formas are more likely to mitigate an incentive alignment problem when they help forecast earnings.</p>