United Parcel Service Inc (UPS) experienced a significant intraday plummet of 5.99% on Monday, as the stock faced heavy selling pressure during the trading session.

The sharp decline was primarily driven by Amazon.com's announcement that it is opening its extensive logistics and supply chain network to other businesses. Amazon's new "Amazon Supply Chain Services" allows companies across various industries to use Amazon's infrastructure, including its fleet of cargo planes and vast network of warehouses, to move, store, and deliver products. This move positions Amazon as a direct competitor to established logistics heavyweights like UPS and FedEx, potentially intensifying competition on pricing and delivery speed.

Additionally, investor sentiment was weighed down by UPS's first-quarter earnings report, which showed strong results but was overshadowed by management's decision to maintain its full-year financial outlook unchanged. This disappointed investors seeking confirmation of a sustained recovery trajectory, especially as the company undergoes a costly strategic transformation to optimize its package mix and network efficiency.