A federal judge has temporarily halted the proposed acquisition of Warner Bros. Discovery by Paramount Skydance, as she reviews antitrust concerns raised by a coalition of 12 Democratic state attorneys general. The $110 billion deal, announced earlier this year, faces scrutiny under the Clayton Act over possible reductions in competition within the film industry, particularly in theatrical movie distribution.

U.S. District Judge Araceli Martinez-Olguin ruled Monday that the states are likely to succeed on their main claim that the merger would substantially lessen competition in the market for wide-release theatrical films. Central to the judge’s decision was an increase in market concentration measured by the Herfindahl-Hirschman Index (HHI), a longstanding antitrust metric that quantifies the competitiveness of an industry based on firms’ market shares. The combined entity would control approximately 27% of the wide-release theatrical distribution market.

According to the states’ calculations, the HHI for theatrical distribution would rise from 1,715 to 2,074 following the merger, marking a significant increase in concentration. By prior Justice Department guidelines, an HHI score in that range signals a moderately concentrated market likely to face competitive harm from merger activity, though updated federal fusion standards under the Biden administration have lowered those thresholds and remain advisory rather than binding on courts.

The dispute highlights an ongoing debate over defining relevant markets in antitrust cases. Critics of the judge’s approach argue that focusing narrowly on theatrical releases is outdated, given the rapid growth of streaming platforms which now generate significantly greater revenue than box office ticket sales. For example, last year domestic box office revenue totaled $8.9 billion, while streaming services such as Netflix and Disney Plus earned $45 billion and $12 billion respectively. Paramount’s own streaming revenue was approximately $7 billion.

Opponents of the merger contend the deal could diminish diversity of viewpoints and reduce opportunities for films to premiere on the big screen, a concern shared by some Hollywood unions. However, supporters, including AMC Theaters CEO Adam Aron, have voiced support for the merger, suggesting it may not harm the theatrical exhibition sector.

Paramount is expected to present arguments and evidence next month to demonstrate the merger’s pro-competitive benefits. Meanwhile, some observers see the broader opposition as politically motivated, particularly given Paramount CEO David Ellison’s recent appointments and perceived alignment with former President Donald Trump. Critics express concern about consolidation of media outlets, specifically the combination of CBS, controlled by Paramount, and Warner Bros. Discovery’s CNN.

Regardless of political considerations, the merged company would carry a substantial debt burden. Whether the deal succeeds on business grounds remains uncertain, but the current legal impasse underscores the challenges in applying traditional antitrust analyses to an evolving media landscape where streaming and digital content have transformed market dynamics.