For members seeking restrictions who don't get the blessing of the applicant company, if the EU grants an approval for a crop, they must make 'compelling grounds' arguments for a unilateral restriction. It may be a difficult argument to win.
This is the first time they have been able to do so since the EU started regulating the technology more than 20 years ago.
When the deadline for exercising the right expired on 3rd October, it ended a transitional period where member states could take the 'easy option' to restrict GM cultivation in part or all of their territories. There will be other chances later, but with more substantial hurdles.
Indeed, crops can even be authorised where the majority of members are opposed, under rules that state that crops permitted in one state can be grown in any (this happened with Novartis BT176 maize in the 1990s, for example).
Some member states and regions have resisted by establishing the GMO-Free Network and invoking so-called 'safeguard clauses' that permit temporary bans on a crop at national level where new information demonstrates a risk to human health or the environment.
Some members have also pushed for greater freedom to restrict cultivation at national level, while the Commission has been delaying authorising new crops to avoid conflict.
The European Court of Justice condemned the Commission for these delays in 2013. There has also been the possibility for further action before the World Trade Organisation, as the situation mirrors a previous de facto moratorium that ran between 1999 and 2003 and was condemned by the WTO following pressure from the US and Canada.
The new approach
The Commission proposed the new rules back in 2010. It proposed that risk assessment and management would remain harmonised at the EU level, while members could impose post-authorisation restrictions.
After much wrangling, this led to Directive 2015/412 coming into force in April. It aims to give more sceptical states such as Austria and Italy the freedom to choose to prevent cultivation while potentially enabling more enthusiastic territories such as Spain and England to cultivate crops that have not yet been authorised.
The Directive allows member states to request geographical restrictions while a crop is being authorised (or reauthorised) without providing reasons, subject to the applicant biotech company not objecting.
In the case of crops that are already authorised, member states can unilaterally impose restrictions if they can demonstrate they are necessary to protect a 'compelling ground' (the directive contains a non-exhaustive list). The company and other interested parties can raise a legal challenge, however.
The transitional phase that ended on 3rd October enabled members to use the first option to prevent cultivation of the one GM crop with EU authorisation - Monsanto's MON810 maize - and the eight crop applications going through the authorisation process.
Of the 19 member states which met the deadline to apply to prevent GM cultivation, the first two have already been waved through by the biotech companies in question and the remainder look likely to receive the same treatment.
The hope from the companies is that these members will be willing to vote in favour of authorisations in future, or at least not attempt to block them - and that they will lift their safeguard-clause bans and not resort to new ones, since they feed wider concerns over safety.
The longer-term position is less clear. Preliminary findings from my research funded by the British Academy, involving interviews of member representatives, indicate that the opt-out will make some states less likely to create safeguard measures, but have little to no impact on votes on authorisations.
It is true that crops may nonetheless be authorised either by qualified majority votes or by the Commission where there is a hung vote. Where the Commission was wary of forcing through authorisations in the past, it may feel the system is now sufficiently flexible to make this acceptable.
But even then, lack of member support lengthens the process for approving a new crop and removes the incentives for applicant companies to agree to exclude particular territories from their applications or waive their right to challenge a restriction of an existing authorisation.
The EU's GMO food fight may be far from over
You can understand member states feeling that they have to be consistent in their approach to a particular crop at national and EU level, but there is a danger that applicant companies may see no reason to rubber-stamp restrictions if the same countries are going to obstruct them at the EU level anyway.
For members seeking restrictions who don't get the blessing of the applicant company, if the EU grants an approval for a crop, they are then reduced to making 'compelling grounds' arguments for a unilateral restriction. It may be a difficult argument to win.
Justifications on grounds of 'environmental protection' are limited under the Directive. And because the rules permit local restrictions, it makes it harder to argue that an outright prohibition across a whole country is justified.
On the other hand, if member states are prevented from opting out, the danger swings the other way: they may fall back into their well trodden paths and resort to safeguard clauses, threaten to block authorisations and generally make the whole authorisation process tortuous.
So the 3rd October deadline was only one step in this debate. If both the EU's member states and the biotech companies can demonstrate flexibility, more crops might be authorised and safeguard measures might be lifted. Directive 2015/412 would then look like a workable truce.
If not, it will not be long before the EU's long conflict over GM crops resumes.
Mary Dobbs is Lecturer in Law, Queen's University Belfast.