McKesson is trading 4.4% higher at $891.72, with available evidence not establishing a direct cause. - The most relevant company news is its fiscal 2027 adjusted EPS guidance increase, raised to $44.20–$45.00 from $43.80–$44.60. That update followed first-quarter results on August 5, not a new announcement on October 1. - No clear company-specific catalyst published October 1 was found. Healthcare sector context is negative, while major indices are modestly higher; neither clearly explains the sharp gain.