Internal combustion engine exhaust filters

The present invention relates to filter systems for purifying the exhaust gases of internal combustion engines. An engine exhaust filter system comprises a housing and a pleated filter element. The housing includes an inlet and an outlet and defines an exhaust flow path between the inlet and the outlet. The pleated filter element is disposed in the exhaust gas flow path between the inlet and the outlet. The pleated filter element includes a filter medium and at least a first perforated support member, the filter medium being disposed adjacent to the perforated filter support member. The filter medium includes a portion extending beyond the perforated support member comprising a seal that prevents or reduces bypass of unfiltered exhaust gas around the pleated filter element.