Investing.com -- Amazon (NASDAQ: AMZN) launched Amazon Supply Chain Services, expanding its logistics network to third-party shippers beyond its marketplace sellers, according to Stifel analysts who called the market reaction overdone.

The service combines Amazon's freight transportation network, including trailers, intermodal containers and aircraft capacity, with its fulfillment and distribution centers and last-mile delivery fleet. Businesses of all sizes can now access the integrated platform previously available only through Fulfillment by Amazon and Multi-Channel Fulfillment programs.

Transportation stocks sold off sharply Monday following the announcement. C.H. Robinson (NASDAQ: CHRW) and RXO (NYSE: RXO) each dropped nearly 10%, while GXO Logistics (NYSE: GXO) plunged 18% in its worst single-day decline since becoming a public company. Forward Air (NASDAQ: FWRD) fell 24%, and parcel carriers FedEx (NYSE: FDX) and UPS (NYSE: UPS) declined 9% and 10.5%, respectively.

Stifel analysts said the announcement represents a more complete commercial offering but does not materially change Amazon's existing capabilities. The company has offered supply chain services to third parties for over a decade, starting with truck brokerage and expanding to air linehaul, trucking and LTL services.

The analysts believe Amazon's third-party offerings aim to densify in-sourced baseload capacity rather than compete directly with vendor-neutral, higher-service providers. Amazon's service targets price-sensitive customers, similar to how other large shippers offer excess capacity to the market.

Stifel's industry checks found Amazon remains largely absent from most competitive bids. Early indications suggest customers like Procter & Gamble, 3M, Lands End and American Eagle are allocating only commodity freight or inventory connected to Amazon's sales channel.

The analysts maintained Buy ratings on FedEx, UPS, Forward Air and GXO, citing early signs of cycle recovery and supply rationalization in the transportation sector.