if booked as a UA-code-share it get's 100%.
if booked as a continuation of a LH transatlantic segment (must be same ticket, LH-flight#) chances are 2/3, in my experience, that it will also get 100%.
And if you qualify by segments, it will count as one (full) segment anyway (there are no 0.5 segments ...).
Otherwise 50% (500 miminum miles will always be 'guaranteed' by Mileage Plus on any LH segment).
[This message has been edited by Rudi (edited 08-07-2002).]