We have multiple fraudulent checks presented against several different legal entities' accounts, all owned by the same people and with the same address. No suspicion of our customer's activity. With one exception, the fraudulent checks all appear to have the same layout, typeface, font, etc., as if they were done by the same person or organization; they also have the same fake signature. I suspect the theft of legitimate checks from a common postal mail drop. My inclination is to combine the cases and thus the SAR into one, since I suspect the fraudulent checks were created by the same people. Not everyone in the department agrees with that approach.
What have you done, in similar situations? I figured with as much check fraud as there is, that somebody else has been in the same situation.