I am a 56 year old American man, married to a 47 year old German woman. We have been married for 20 years. We are in the process of divorce governed by German law. I am entitled to a pension through my US company.

Is she entitled to a portion of it? Do German courts have authority over American Companies/pension funds, money assets in the US?

If she is entitled, does the payout begin with my retirement or must she wait until her retirement?

I don't know German law, but she might be able to file a QDRO against your american pension. I would suspect, if properly filed, your company would be required to honor it.

Was this pension part of the marriage or outside the marriage? If it was part of the marriage (you accrued it whie married) then she is entitled to a portion of it related to the marriage. If this is something that you had before you were married then she may not be entitled to any of it depending on local laws.