Readers will no doubt remember the outcome of Schalk and Kopf v Austria  ECHR 1996, in which the ECtHR ruled that there was no right under the Convention for same-sex couples to marry. It held that, in the absence of same-sex marriage in Austria, the possibility of entering a registered partnership satisfied the requirements of Article 12 ECHR (right to marry and found a family).
The Constitutional Court of Austria [Verfassungsgerichtshof] has just taken precisely the opposite view.
In a recent decision of 4 December, G 258-259/2017-9, a case brought before by two women living in a registered partnership who petitioned for the right to marry, the Court repealed those provisions which, for the time being, deny same-sex couples access to marriage. The repeal will take effect as of the end of 31 December 2018 and, on the same date, registered partnerships will become available to opposite-sex couples. The Court held that
“The resulting discriminating effect is reflected in the fact that, on account of the different terms used to designate a person’s marital status (‘married’ vs. ‘living in a registered partnership’), persons living in a same-sex partnership have to disclose their sexual orientation even in situations in which it is not and must not be of any significance and, especially against the historical background of this issue, they are at risk of being discriminated against” … [Therefore] “The distinction of the law between opposite-sex and same-sex relationships as two different legal institutions violates the principle of equal treatment, which forbids any discrimination of individuals on grounds of personal characteristics, such as their sexual orientation.”
Which, as it happens, also resolves in an unexpected way the issue recently decided by the ECtHR in Ratzenböck and Seydl v Austria  ECHR 947, in which the applicants, Helga Ratzenböck and Martin Seydl, complained unsuccessfully that, as a heterosexual couple, they were denied access to a registered partnership under Austrian law.