A few sources around, here’s one from https://news.law.fordham.edu/jcfl/2024/03/13/understanding-amazons-alleged-anticompetitive-practice:

the FTC claims Amazon punishes third-party sellers for offering lower prices on other websites.[2]

Select Competitor – Featured Offer Disqualification (SC-FOD).[6] SC-FOD is an algorithm that prevents a seller from “winning the Buy Box” if it finds that the seller sells that product for less on a Select Competitor’s website.[7]

References for 2, 6, 7:

[2] Complaint at 85, FTC v. Amazon, W.D. Wash. Case No. 2:23-cv-01495-JHC (Nov. 2, 2023).