First, ACT took New Zealand First's policy of lowering the number of MPs - and now David Seymour says Winston Peters has stolen a policy of his own.
On Sunday, at New Zealand First's AGM in Tauranga, the party voted to proceed with the Respecting New Zealand Values Bill.
According to New Zealand First MP Clayton Mitchell, the Bill would force immigrants and refugees to "accept, respect and adhere to the tolerance our society expects", including reportedly respect for gender equality, religious freedom and New Zealand law.
ACT Party leader David Seymour says the policy is nothing new.
"It's not surprising [New Zealand First's] only sensible idea this parliamentary term has come straight from the ACT Party website," he said.
Mr Seymour added that the party had "shown a glimmer of sense after a week of terrible law-making".
The Green Party, which supports the Labour-New Zealand First coalition Government, doesn't think the Bill is sensible though.
Green Party Immigration spokesperson Golriz Ghahraman said the Bill wasn't a priority for Parliament, and it was important debate about immigration didn't "bring out racist sentiments that can cause real harm".
"NZ values certainly don't include degrading other culturesâ€¦ let's not forget being judged by our worst would mean NZ culture = domestic/sexual violence, youth suicide, and indigenous abuse," she wrote on Twitter.
Ms Ghahraman also acknowledged New Zealand First MP and Minister Tracey Martin's concern with the Bill.
The National Party looks like it won't support the Bill saying "we don't want to dignify this with a response".
Mr Seymour may want to check his record in stealing policies as his party recently took one of New Zealand First's.
In August, ACT unveiled a plan to cut the number of MPs to 100, drop the Maori seats, and limit the number of ministers to 20.
It was awkwardly similar to New Zealand First's smaller government policy the party campaigned on in last year's general election.
Mr Seymour later admitted to stealing the idea.
"Even Winston Peters has a good idea from time to time, and we've stolen his only good one."
The pair have had a contentious parliamentary relationship, including Mr Seymour calling Mr Peters a "charismatic crook" and "a likeable rogue... who's done a lot of damage to the country".
He even went so far as to say he would "shoot Winston Peters, just to do New Zealand a favour," when he partook in a round of "shoot, shag, marry".
Mr Peters has joked about ACT's sole MP as well. He noted Mr Seymour's Dancing with the Stars stint and called him "the Fred Astaire of the South Pacific... what a frightful sight that is".