Upvote:2
@phoog is correct. This is explained in Schengen Borders Code (amended) in article 6:
- For intended stays on the territory of the Member States of a duration of no more than 90 days in any 180-day period, which entails considering the 180-day period preceding each day of stay, the entry conditions for third-country nationals shall be the following...
"Member States" here means those who signed the Schengen agreement.
Decision No 565/2014/EU asks (Article 5) RO/BG/CR to accept Schengen visas (and residency permits) in lieu of national visas for entry into RO/BG/CR. If they are accepted, they must be accepted under standard 90/180 rule (article 2). It does not make Romania the "Member state", and 90/180 rule would in this case apply independently.
Looking at this particular text:
The entry conditions for third-country nationals whose intended stays on the territory of the Member States have a duration of no more than 90 days in any 180-day period ... in so far as this Decision sets up a regime of unilateral recognition by Bulgaria, Croatia, Cyprus and Romania of certain documents issued by Member States fully implementing the Schengen acquis ... for transit through or intended stays on their territories not exceeding 90 days in any 180-day period.
it seems pretty clear that it makes difference between 90/180 days on the territory "of Member States", and "on their territories"
PS. The above is of course non-legal opinion - if you need an official legal opinion, you should consult a lawyer.