Star Alliance - earning miles on codeshares

I'm aware that one can never earn miles on *A marketed flights when the operating carrier is not a *A member. What about the other way around? In United Mileage Plus I am 95% certain both the marketing carrier and operating carrier have to be *A to earn miles. Is it also the case in other FF programs? The specific flight I have in mind is a Singapore flight with an Air India flight #, but also interested in the general answer. Thanks

In United Mileage Plus I am 95% certain both the marketing carrier and operating carrier have to be *A to earn miles.
Sorry to say you're 95% mistaken. With the exception of Air China operated flights, it makes no difference at all who markets the flight - it's only the operator that matters.

Sorry to say you're 95% mistaken. With the exception of Air China operated flights, it makes no difference at all who markets the flight - it's only the operator that matters.

This thread (http://www.flyertalk.com/forum/united-mileage-plus/804654-mile-credit-air-india-ticket-tg-metal.html) seems to indicate otherwise.

On BD, the rule conforms to what aau states, viz. both must be *A. That said, you can occasionally get lucky and get credit for a non-*A marketed but *A-operated flight, depending on the station and airline.

Sorry to say you're 95% mistaken. With the exception of Air China operated flights, it makes no difference at all who markets the flight - it's only the operator that matters.

That is incorrect. For example if you book Aircalin codeshare on Air NZ, you will not be able to credit to Mileage Plus.