A spokesman for Mr Cunliffe would not say whether the leader believed he should have to declare the donations, but said his register entry would contain all information that was required by the rules.
Mr Robertson also said he would stick to the rules but would not say whether that should include the donations. Mr Jones said he would discuss it with Sir Maarten next week. He would not say whether he received any help over the $500 threshold.
Sir Maarten said Labour's new United States primaries-style leadership campaigns, which had a fundraising element, were new to NZ and no specific consideration had yet been given to whether the Register of Pecuniary Interests should apply.
The rules for the register are decided on by a committee of MPs and set out in the standing orders that form Parliament's rules.
Labour's leadership contest rules did require contestants to declare donations of more than $1500 to the party's ruling council, but said they would not be publicly disclosed.
The donations did not have to be declared to the Electoral Commission because they were not for an election. In elections, candidates must disclose gifts of more than $1500 and parties must disclose more than $15,000.