This proposal seeks to strengthen shareholder rights and enhance board accountability by giving shareholders a meaningful mechanism to convene a special shareholder meeting. As United Therapeutics navigates a complex and highly regulated biotechnology landscape focused on rare and life-threatening diseases, shareholders must be able to address urgent concerns between annual meetings if the Board proves unresponsive to issues that could materially affect long-term value. A substantial majority of large U.S. corporations provide shareholders with the right to call special meetings. As of mid-2025, approximately 76% of S&P 500 companies allow shareholders to call special meetings, subject to ownership thresholds and procedures.1 This reflects a clear market trend toward enhancing shareholder engagement and aligns governance practices with investor expectations. Major institutional investors ? including BlackRock, Vanguard, and State Street ? have voting guidelines shareholder rights to call special meetings. BlackRock's proxy voting guidelines explicitly state that "[s]hareholders should have the right to call a special meeting," recognizing that this right strengthens accountability. State Street's stewardship policies also emphasize "shareholder protection" and vote in support of governance enhancements that promote long-term economic value. Vanguard has also supported governance proposals related to shareholder rights in special meetings. Giving shareholders the ability to call special meetings ensures the Board remains attentive to investor concerns on performance, strategy, or governance. Without this right, shareholders are limited to waiting for the next annual meeting, even when urgent issues arise that could materially affect long-term value. This right also serves as a backstop to complacency, encouraging the Board and management to engage substantively with shareholders. A meaningful special-meeting mechanism complements other governance rights and enhances investor confidence in the company's oversight. According to "What Matters in Corporate Governance" by Lucien Bebchuk et al. of Harvard Law School, the inability of shareholders to call special meetings is one of six entrenchment mechanisms negatively associated with company performance.2 Unchecked entrenchment is particularly deleterious to the company's diversified shareholders, who have an interest in ensuring that our Company's board or management does not lead the company towards profiting from practices that threaten the macroeconomy and, by extension, their portfolio returns.3 With the widespread use of online and hybrid shareholder meetings, conducting special meetings is more practical and cost-effective than ever. There is no logistical barrier that justifies withholding this right from shareholders. Empowering shareholders to call special meetings aligns our Company with prevailing governance norms, supports stewardship policies, and strengthens board accountability. 1 https://www.gibsondunn.com/wp-content/uploads/2025/08/DC-Shareholder-Proposal- Developments-Proxy-Season-080625.pdf 2 https://www.jstor.org/stable/30226006 3 https://theshareholdercommons.com/theory/