@tintern55 ,
@robtm , I am not sure I understand the comment about foreign vs. domestic share and recognition thereof. As I read the material from the merger, all it implies is that your X number of Praxair shares were sold for $163.45 and you bought X number of ( obviously involuntary conversion ) Linde shares for $163.45 each. Thus you have to recognize the gain in the year it occurred i.e. 2018. So the gain is based on your old basis and the exchange price ( 163.45 ) and your new basis is $163.45 per sh. going forward. Thus you need to file an amended return to cover the gain ( assuming you have held the Parair shares for more than 1 year.
