THE US Congress is considering legislation to strip carriers of antitrust immunity that would make it harder to operate in alliances or vessel-sharing agreements, reports New York's Journal of Commerce.

Congress will debates whether ocean carriers were engaged in collusion and price gouging that resulted in soaring freight rates and historically high profits. Or were these phenomena the result of demand exceeding supply?

Many believe that a loss of antitrust immunity would trigger yet another round of mergers as carriers withdraw from alliances and second-tier carriers finding themselves too small to compete, forcing them to merge.

Ever since US Democratic President Joe Biden quipped last year that he wanted to "pop" carriers for raising rates ten-fold, reality was set aside as carriers proved to be a convenient scapegoat for problems such as inflation that threatens electoral fortunes of the Democratic administration.

Rates and profits rocketed due to a consumer spending surge and capacity being removed from the market as ships were forced to wait for berths outside congested seaports.

As soon as those conditions eased, rates promptly collapsed, falling more than 90 per cent in the transpacific trade since last year. Supply and demand drove the market up, and then down.

During his State of the Union address in January, President Biden urged Congress to "finish the job," going beyond last year's Ocean Shipping Reform Act of 2022 (OSRA-22) by passing "bipartisan legislation to strengthen antitrust enforcement."

If collusion has occurred, it hasn't been visible to the agency with the most knowledge of the industry, the US Federal Maritime Commission (FMC).

The transpacific trade "is not concentrated, and the increased rates in that market are the result of an extreme spike of consumer demand that overwhelmed the supply of ship capacity," the FMC said in its Fact Finding 29 study.

"Even after increasing our reporting and analysis, there's no evidence" of collusion or price fixing by carrier alliances, said FMC chairman Daniel Maffei.