Last Tuesday, the European Union's top court ordered Poland to recognise the marriage of a same-sex couple, who had wed in Germany.
In delivering its verdict, the Court of Justice of the European Union (CJEU) kept the language broad, referring to the obligation of "a member state" to recognise same-sex marriages registered in other EU member states.
It means that a Czech, Romanian or Bulgarian court - or any other EU member state where same-sex marriage is not recognised - will now have to take the verdict into consideration if a similar case arises in their jurisdiction.
The case in question involved a married Polish couple, Jakub Cupriak-Trojan and Mateusz Trojan, who tied the knot in Berlin in 2018 while residing in Germany.
When they returned to live in Poland the following year, they tried to register their marriage at Warsaw's civil registry office. However, that request was declined on the basis that Polish law recognises marriage as a union between a man and a woman.
The couple appealed that decision in 2020 at a Polish regional court, arguing that non-recognition of their marriage restricted their freedom of movement, on the basis that they were unable to live the same private life in Poland as they had enjoyed in Germany as a married couple.
But when that appeal was rejected, they took their case to Poland's Supreme Administrative Court, which referred the case to the CJEU in 2023.
In issuing its verdict this week, the court found that the refusal of Polish authorities to recognise the marriage could not be justified as it breached EU law on safeguarding "respect for private and family life".
Polish authorities, the court found, had left the couple "in a legal limbo" and had failed to meet the "fundamental needs of recognition and protection of same-sex couples in a stable relationship".
LGBTQ+ groups across Poland welcomed the decision.
"It is a milestone, it is a huge change, maybe even a revolution," Artur Kula, one of the lawyers who represented the couple in the case, told RTÉ News.
The case, he said, was about having a "coherent EU legal system" so that EU citizens "are treated the same way in each member state".
Mr Kula said that while Polish authorities will now have to recognise his clients’ marital status because of the CJEU’s decision, they may still have to fight for full taxation, inheritance, property and pension rights through other administrative processes.
The Luxembourg court also ruled that freedom of movement allows EU citizens, who have "created or strengthened" a family life in one member state, to continue their family life when they return to live in their own country.
That effectively rules out the possibility of so-called 'marriage tourism' whereby couples could travel to an EU member state where same-sex marriage is recognised, and then return to their home country to request recognition of their marital status.
The CJEU is clear that couples need to have built a life as a married couple elsewhere first.
Marriage equality legislation, enshrined by most western European governments over the past two decades, has generally not been replicated in the east of the continent where more conservative attitudes towards same-sex relationships still prevail.
Same-sex marriage is legal in just two eastern EU member states: Estonia and Slovenia.
Czechia, Hungary, Latvia and Lithuania all have civil partnerships for same-sex couples.
In Poland’s case, attitudes towards legal recognition of same-sex relationships are becoming more positive.
Recent polls show that support for civil partnerships hovers just below 60%.
An Ipsos survey last year showed that 39% of Poles supported same-sex marriage.
The general view is that Polish voters hold more progressive views than most of their elected politicians on the issue.
Maja Heban, spokesperson for Love Does Not Exclude, a Polish NGO campaigning for marriage equality, described the CJEU verdict as "a huge deal", although she said it would not have an immediate impact on the lives of Polish same-sex couples who have always resided in Poland.
"This ruling is valuable in the way that it gives us a tool to have this precedent of the very first Polish marriage certificates, issued by Polish officials for same-sex couples," she said.
"I think being able to just hold a marriage certificate in their hand, and see this official Polish document that says: Yes, this woman and this woman are a married couple. I think that, in itself, is emotionally, symbolically, extremely powerful."
The number of married same-sex couples who have returned to live in Poland from other EU member states is believed to be small, perhaps numbering in the hundreds.
Poland's justice minister said this week that the country's authorities would implement the CJEU's decision, while a minister at the prime minister's office, Katarzyna Kotula, in charge of equality issues, welcomed what she called "a historic ruling".
However, the office of the country's conservative President Karol Nawrocki criticised the verdict.
Mr Nawrocki has previously said that he opposes any changes to Poland's current marriage law, a view that is in line with the main opposition and nationalist Law and Justice party.
Polish Prime Minister Donald Tusk's centre-right party said it would deliver civil partnership for couples regardless of their gender when elected two years ago.
But opposition from two smaller conservative parties within the coalition government to the original proposal has resulted in a watered-down bill that proposes legally recognising people who have a close relationship, and would afford some joint taxation and inheritance rights.
The wording of the proposed bill does not make a reference to same-sex couples, the rights of same-sex couples who have children, nor does it reference adoption.
Many Polish LGBTQ+ rights groups believe that the amended bill does not go far enough and have stayed away from supporting it.
There is a good chance that even if the bill passes through parliament, Mr Nawrocki will use his presidential veto to stop it from becoming law. Last month, he said he would oppose any bill that tried to introduce "quasi-marriage".
Jakub Jaraczewski, a Polish legal expert on EU rule-of-law, said Tuesday's verdict from the CJEU "opens a way towards the legalisation of same-sex unions" in Poland.
"This is the CJEU saying to Poland, you have to recognize these unions, and it's putting an obligation on the country to implement this judgment.
"So, this is the strongest possible expression that the CJEU could have made in this situation," said Mr Jaraczewski, a researcher with Democracy Reporting International, a Berlin-based think tank.
This week's ruling from the EU's top court may tempt more same-sex married couples to move back to their home countries, knowing that their national courts must now recognise their marital status.
But beyond the initial joy of receiving official recognition of their marriage, they are likely to face more bureaucratic hurdles to acquire the same, full legal rights that other married couples enjoy.
