@HansPeter
>"There is a starship in orbit around earth. X happens so that starship has more fuel than before X happened. This is planned to be two starships docking and transferring fuel from one to the other."

So this is fairly clear that one Starship transferring propellant to another is enough. Fully refuelling a Starship which may require fuel transfers from several Starships is not required.

What I am less clear about is if there is one attempt that does not fully succeed - say it transfers only 5% of the propellants that is supposed to be transferred. This would seem like refuelling is not "solved" and per question title should resolve no but per your comment there is more fuel so might resolve yes.

There is also a potential issue with your comment that you use term "fuel". If methane fuel was transferred but liquid oxygen, the oxidant was not, it is not successful, nor much use, but there is more "fuel" than before the transfer. So per your comment that might resolve yes? I suggest it would be better to specify what is required in terms of both methane and LOX.

So is
Transferring some (but significantly less than intended) methane and no LOX sufficient to resolve yes?
Transferring some (but significantly less than intended) methane and some Lox sufficient to resolve yes?
Transferring over 50% of intended amount of methane but no LOX sufficient to resolve yes?
Transferring over 50% of intended amount of methane and over 50% of intended amount of LOX sufficient to resolve yes?
Transferring substantially all (90%?) intended amounts of each of methane and LOX sufficient to resolve yes?
or something else?

@ChristopherRandles the difficult problem from what I understand is achieving any transfer at all. So if more than 1kg oxidiser and 1kg fuel (whatever they might be) are transferred I assume the problem is essentially solved and will resolve as yes.

Will there be at least one successful refuelling in orbit of a starship by end of 2025?

I don't understand the resolution criteria?

@ElliotDavies There is a starship in orbit around earth. X happens so that starship has more fuel than before X happened. This is planned to be two starships docking and transferring fuel from one to the other.

@HansPeter there's also been discussion about having a propellent depot that will accumulate propellent on-orbit. After enough propellent has been launched and transferred to the depot, a deep space Starship (bound for the Moon or Mars) will rendezvous with the depot and take it all.

The depot may be a Starship variant. Or it could be something smaller, lofted into space as a payload. Or maybe all refueling will be done Starship-to-Starship, and the depot was just people speculating.

If SpaceX transfers propellent from a a Starship to a depot like vehicle, will that be enough to resolve YES? Or would the depot need to transfer propellent to something that's decidedly Starship shaped before it counts?

Also, does a Starship need to take on a useful amount to count, or small test quantities are enough?

<deleted>

@DanHomerick pretty sure the depot will also be a starship (depot variant of starship, likely without flaps or tiles, probably stretched tanks)