Sen. Richard Blumenthal (D-Conn.) was welcoming Amazon's decision Monday to drop the most-favored-nation (MFN) clauses for members of its online marketplace. Amazon had required third-party merchants on its site to agree to terms that prohibited them from offering those goods at lower prices on other platforms, meaning that if a platform had lower transaction fees, the seller could not pass those savings on to customers but would have to charge them no less than the Amazon price.

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Blumenthal has been a critic of the terms, which Amazon stopped enforcing in Europe over a half decade ago under pressure from the EU.But Blumenthal was suggesting that Amazon's move was more akin to the performance review: 'works well when trapped like a rat," and that there were more that needed trapping."“Amazon’s wise and welcome decision comes only after aggressive advocacy and attention that compelled Amazon to abandon its abusive contract clause," he said. "I remain deeply troubled that federal regulators responsible for cracking down on anti-competitive practices seem asleep at the wheel, at great cost to American innovation and consumers. The DOJ and FTC must begin aggressively investigating Big Tech’s potential antitrust violations and take necessary enforcement actions to deter more harmful behavior.”The senator pointed out that he wrote the Federal Trade Commission and the Department of Justice back in December to "demand" an investigation into the "price parity" provisoins of the Amazon contracts. He also raised the issue at a haering last week on the economy.