In the Dutch Intelligence and Security Services Act referendum, 2018, preliminary results indicate 47.3% of votes in favour and 48.8% of votes in opposition, with the remaining votes blank and a turnout of 51.4%. The referendum is valid in recommending to overturn the law if turnout exceeds 30% and a majority votes in opposition. How is this majority counted? Does it need to be >50%, or is exceeding the votes in favour sufficient?
The Kiesraad has issued a statement via Twitter:
De Wet raadgevend referendum laat zich niet expliciet uit over vraag wanneer sprake is van een meerderheid. Volgens Kiesraad is sprake van meerderheid tegen de wet als, bij voldoende opkomst, percentage kiezers met geldige stem tegen hoger is dan percentage geldige stemmen vóór.
The Law advisory referendum does not explicitly clarify when there is a majority. According to the Kiesraad there is a majority against the law when, with sufficient turnout, the number of valid votes against is larger than the number of valid votes in favour.
So the answer to the question is: Yes, it is.
You may find this as a useful, but not complete answer to your question:
Should this turnout threshold be reached and should a majority of voters reject the Act, two possibilities are open to the government. One possibility is to act in accordance with the results and propose a bill to repeal the Act. The other option is to propose a bill to have the Act nevertheless enter into force: For the results of an advisory referendum are not binding.