I wouldn't get hung up over trying to figure out how the ownership of the account ought to be, and go with what you've got now. If, based on your deposit contract, John and Mary are co-owners, complete the CTR as if the account is joint -- Check "multiple persons" in item 1, put Mary in Section A on the front, check box (e) in Section B for "conducted on own behalf," and put John in Section A on the back. Go back and plug "Doe's Construction" in item 5 on the front of the form.
You don't know who the owner of the business is, and you shouldn't assume it is John (for what it's worth, I would have done the same).
Get the CTR filed. Then worry about whether the account is set up properly later. You might have a sole proprietorship, but you might also have a de facto partnership. Then you can concern yourself, if necessary, with whether the account can be a NOW account.
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John S. Burnett
BankersOnline.com
Fighting for Compliance since 1976
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