A spokeswoman for the country's Electoral Council confirmed to Reuters that a sampling of names had been checked to verify they were those of registered voters, but not whether the signatures themselves were real.
"The Dutch referendum law does not require the signatures to be verified," said Heleen Hörmann.
"When we evaluated the law we raised concerns ... about the process. There is no way for the signatures to be verified because they were never entered in the system," Hörmann explained.
The council had recommended that the government use its national digital identification system, known by the acronym DigiD, for the referendum application, but that advice was not adopted, she said.
On April 6, 2016, a referendum on the EU-Ukraine association deal took place in the Netherlands. 36 percent of voters supported the ratification of the agreement while 64 percent said "no." The turnout made 32 percent.