Miles & More (Lufthansa, Austrian, Swiss, and other partners) - Mile "sponsership" on LH

I have a couple travelling with me in Jan on an LH flight to Miami. Now their sister in law "sponsered their flight in C using her miles BUT the sponser will not be on the flight with them. Do they need to bring any thing with them confirming their sponsor or do I need to worry about anything in this case???

No. Only thing you could be asked for is the credit card used to pay the taxes (could also be another form of identification such as Miles&More card). I've never been asked for this but the rules say you are to have it with you.

Mario they don't have a M&M card that is why the SiL sponsered them however won't a passport be enough as ID or did I just misunderstand what sort of ID you were refering to....

MR is correct , technically you need a copy of the credit card.
I have done this many many times for relatives , never had an issue , they were never asked for cc.

But I guess there is always a first.

Normally when booking an award with M&M there is some mean of "identification" associated with that booking (e.g. the credit card used to pay the taxes, the M&M card, etc.). Now I understand the person who booked the award is not on that flight which isn't a real problem, because passports plus a printout of the booking confirmation (which the sponsor should have received by email) should be enough (assuming the names are spelled right :)).

I frequently sponsor flights from Germany to the US for my parents and they never had a problem. Since you are flying LH the couple can also use online check-in, so they will already have their BPs before coming to the airport. The booking code and travellers' names are sufficient to check-in online on LH's website (again assuming the departure location allows online check-in).

Hope this helps!

I booked tickets for my mother and other relatives (with Lufthansa and other wirlines) using LH miles.
Never any problem as long as the person had the printout of the reservation and a matching ID.

Since you are flying LH the couple can also use online check-in, so they will already have their BPs before coming to the airport. The booking code and travellers' names are sufficient to check-in online on LH's website (again assuming the departure location allows online check-in).

Hope this helps!

Second that.

I'd definitely recommend obtaining BP online beforehand. BP + Passport works at least for my in-laws whenever they use our LH miles ex FRA.

Even better is using the actual traveller's Credit Card (not: sponsor's M&M or sponsor's credit card) to pay fee & taxes, as this would do away with any questions whatsoever.

LH don't seem to have a procedure in place to verify CC used.
CX,TG and BA for example do however.

LH don't seem to have a procedure in place to verify CC used.
CX,TG and BA for example do however.

Now that you've said it... I'll try that on LH. Usually I check in with my M&M/CC combined card. It'll be TXL-MUC-TLV on Monday and let's see if I they take me along with just a passport.