I was sorry to see you didn't get a real answer to your question because I have a similar situation in knowing how to handle the discount rate that needs to be reported as ordinary income at the time of sale. I know the cost basis is spread over both companies, but I can't find anything on the internet that explains how the discount is handled - does it spread over both company's stock at the same rate the cost basis does, does the discount fully stay with the original company's stock (which parallels what you did in reporting it all when you sold "Company A's stock"), or is there a completely different way the discount splits / spreads?
If you ever figured it out or confirmed how via other sources, I'd sure love to know. Thanks.
