Gambling giant Tabcorp has threatened legal action against competitors Ladbrokes and Neds as it seeks to tear up a partnership that jeopardises its lucrative monopoly in New South Wales pubs and raises the prospect of more betting ads inside venues.

The dispute highlights the increasingly competitive sports gambling industry in Australia, with companies battling for a larger share of the multibillion-dollar market. Tabcorp, traditionally known for in-store betting, is now prioritising online wagering in direct competition with Labrokes and Neds.

In October last year, Entain Australia announced a “groundbreaking new agreement” with the powerful Australian Hotels Association (AHA) to increase gambling competition inside the state’s pubs. The deal would allow Entain to promote its Ladbrokes and Neds brands and create designated zones for customers.

Tabcorp, which has an exclusive deal with the NSW government to operate retail wagering inside pubs and hotels, believes the partnership may breach its license.

The partnership also raises the prospect of more sports gambling promotions inside pubs at a time when politicians and health advocates are increasingly critical of the industry’s operations, citing “powerful evidence” of community harm.

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On Wednesday, NSW supreme court justice James Stevenson ordered Tabcorp be provided with legal advice and details on how the partnership would work in practice, which would inform any legal action to stop it. This includes details on proposed “VIP Ladbrokes activation zones” or “Neds Club lounges” inside pubs.

Tabcorp successfully argued there was not enough publicly available information to confirm its suspicion the partnership would violate its license deal.

“Tabcorp will review the documents disclosed in order to assess whether or not to commence legal proceedings against Entain or AHA NSW, or both, in the supreme court,” a Tabcorp spokesman said.

The supreme court judgement reveals the AHA wrote to Tabcorp in October to stress it was “committed to supporting Tabcorp’s exclusive and long-term retail wagering licence in NSW hotels”.

“It also remains our position that none of the arrangements as announced by AHA NSW and Entain do anything to undermine Tabcorp’s retail exclusivity, nor are they in contravention of any laws, including the Unlawful Gambling Act,” the letter said.

When the partnership was announced, the AHA NSW chief executive, John Whelan, said many hotels were operating Tabcorp facilities at “significant losses” and that change was necessary.

“Today’s partnership with a world leader in Entain will finally give NSW hotels competition and choice,” Whelan said in October.

Entain Australia’s chief executive, Dean Shannon, said the partnership would allow it to “connect and communicate” with a valuable audience inside pubs.

“There is no reason why traditional cash wagering can’t coexist in a hotel, alongside an advertising sponsorship arrangement with Entain that promotes the digital offering of one of our leading brands,” Shannon said in October.

A spokesperson for Entain acknowledged the supreme court judgment “granting preliminary discover of documents on three of eight requested categories”.

“Entain is building great momentum in the rollout of its digital wagering sponsorships and is pleased with the high levels of interest from pubs across NSW,” the spokesperson said.