<Table> <Tr> <Td> </Td> <Td> This article relies largely or entirely on a single source . Relevant discussion may be found on the talk page . Please help improve this article by introducing citations to additional sources . (December 2011) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article relies largely or entirely on a single source . Relevant discussion may be found on the talk page . Please help improve this article by introducing citations to additional sources . (December 2011) </Td> </Tr> <P> In financial regulation, a Suspicious Activity Report (SAR) or Suspicious Transaction Report (STR) is a report made by a financial institution about suspicious or potentially suspicious activity . The criteria to decide when a report must be made varies from country to country but generally is any financial transaction that does not make sense to the financial institution, is unusual for that particular client or appears to be done only for the purpose of hiding or obfuscating a transaction . The report is filed with that country's financial crime enforcement unit, which is typically a specialist agency designed to collect and analyse transactions and report these to relevant law enforcement units . Front line staff in the financial institution have the responsibility to identify transactions that may be suspicious and these are reported to a designated person that is responsible for the reporting the transaction . The financial institution is not allowed to inform the client or the parties to the transaction that a SAR has been lodged . </P> <P> For example, in the United States, suspicious transaction reports must be reported to the Financial Crimes Enforcement Network (FinCEN), an agency of the United States Department of the Treasury . In Australia the SAR must be reported to Australian Transaction Reports and Analysis Centre (AUSTRAC), an Australian government agency . Most countries have laws that require financial institutions to report transactions and will have a designated agency to receive these . The agency to which a report is required to be filed for a given country is typically part of the law enforcement or financial regulatory department of that country . </P>

What is a common reason to file a suspicious activity report
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