Palantir stock dropped today primarily due to a report about "very high risk" and fundamental security flaws identified by a U.S. Army internal memo in a battlefield communications system (Next Generation Command and Control, NGC2) that Palantir is developing with defense partner Anduril Industries. The memo highlighted issues such as lack of control over user access, inadequate logging, vulnerabilities to insider threats, and external attacks, leading to investor concerns about contract and reputational risks. This caused a swift sell-off, pushing the stock down approximately 7.5% during the day. Despite Palantir and Anduril denying these claims, calling the memo outdated and inaccurate, and stating no vulnerabilities were found in Palantir's platform, the stock was affected by the negative sentiment and broader tech sector weakness. The security concerns cast doubt on the battlefield communications project, which is critical given Palantir's Pentagon contracts and defense- related business. The drop triggered technical selling rules after the stock recently cleared a buy point. In summary, the stock decline today reflects investor reaction to the reported security issues in a key military communication system Palantir is involved with, amplified by broader market tech weakness and ongoing volatility in the stock.