The Papua New Guinea NRL franchise plans to unveil its logo and jersey later this month, alongside a Rugby League World Cup match in Port Moresby on Saturday, October 24.
New Zealand Rugby has filed proceedings in the New Zealand High Court over the team's planned use of the name Chiefs.
It is seeking interim and final injunctions to prevent the Australian Rugby League Commission from using "PNG Chiefs", "Chiefs" or similar names in New Zealand.
NZR says it owns the Chiefs name and logo trademarks, used by Hamilton's Super Rugby team, and has held those rights since 1998.
It also holds Australian trademark protection for the logo, the organisation said.
The expansion team's name was confirmed in October 2025 ahead of its planned 2028 NRL entry.
NZR said it raised concerns with the ARLC but had no "positive outcome", and could not "engage with the ARLC constructively" over the past year.
Chief executive Steve Lancaster said, "For 30 years the Chiefs and their players have built an incredibly strong identity that is widely recognised and loved by fans,"
He added, "We have raised the concerns with the ARLC directly and consistently over the last year in attempting to find a resolution. We now have a responsibility to protect the Chiefs brand."
"We want to be absolutely clear, this is not about rugby league's growth in the Pacific. We welcome the development of the Pacific region through sport and the passion that the people of Papua New Guinea have for both rugby and rugby league," Lancaster said.
NZR argues that both brands operating in the same markets would cause "significant confusion and damage".
It said IP Australia warned of a "real and tangible danger of confusion" when the ARLC sought trademark protection for "PNG Chiefs".