Let's get "real-world" about this. You don't have ID info for the night drop. You won't have ID info for the first two $700 deposits because who gets ID for such small transactions? If you system has "real time" aggregation capability, you might get a red flag when the third $700 deposit is processed, since you're now over the $10K threshold. At that time, you might obtain ID info on the conducting person.
Now the CTR looks something like this: The business is listed in section A as benefiting from the deposits, and the appropriate account is listed in Part 2. The ID for the third runner is in Section B, along with a "night deposit" checkoff, and a "multiple transactions" checkoff. The "multiple transactions" box at the top of the form (item 1) is also checked.
Now, if you follow up on the first three deposits, as suggested by the language cited by Ken (above), you may get ID info on one or more of the transactions -- you might even find out that the same person did all four deposits. If you have ID info on additional persons, you add Section B entries. If you are satisfied that you've got info on all persons, including the runner who made the night drop, you uncheck the two boxes at the top of section B.
Or, if you don't even realize that the CTR trigger is pulled until after the work is processed for the night (common), you make some kind of an effort to determine who made the transactions, probably fail at that, and file a CTR with Section A completed, and section B sporting just the two check marks.
John S. Burnett
Fighting for Compliance since 1976
Bankers' Threads User #8