Not that I know of. Have seen hundreds of millions with no issue.

My next goal is 1,000,000,000      lol

I think the most I ever had was a bit over $380 million.

that's a good chunk. 

Maybe 90 here. Too much rolling during CvC to get higher. :)

250M best I've ever had.  This Artak event cooked my silver though, down to 130M.