rdeheld-535532 (4/24/2013)
Yes It does require licenseRead Multiplexing:
"The number of tiers of hardware or software between the SQL Server and the user or devices that ultimately use its data, services, or functionality does
not affect the number of CALs required:"
Only when some one manualy forwards the emaill containing the report, Then its not required
If the emailed report is static (the data for the report is included in the report) and does not need any direct (or indirect) access to SQL Server, then it isn't multiplexing and no license is required.
If the report requires access to SQL Server to render the report, then yes the user of that report needs a license (CAL) for SQL Server.