What are the business travel federal income tax rules ?

Consider this story (if you’re not a LOST fan, bear with me–don’t worry, there’s no LOST spoiler here!): 

Hurley was the owner of Mr. Cluck’s Fried Chicken.  His business was exploring the possibility of expanding to Australia, so Hurley boarded Oceanic Flight 815 and went to Australia for 3 weeks to meet a potential investor.  While there, Hurley spent 2 weeks sight-seeing and partying.  He spend only one week there meeting with clients. 

 Hurley also brought his employee, Charlie, with him, but paid half of Charlie’s plane ticket, since he couldn’t get any discount travel deals.  Charlie only came for the business meeting and did not spend any personal time in Australia.  

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