0001044321-11-000149 SC 13D 1 20110706 20110706 AUSTIN W. MARXE AWM INVESTMENT COMPANY, INC. DAVID M. GREENHOUSE MG ADVISERS, L.L.C. MGP ADVISERS LIMITED PARTNERSHIP SPECIAL SITUATIONS CAYMAN FUND, L.P. SPECIAL SITUATIONS FUND III QP, L.P. SPECIAL SITUATIONS PRIVATE EQUITY FUND, L.P. SPECIAL SITUATIONS TECHNOLOGY FUND II, L.P. SPECIAL SITUATIONS TECHNOLOGY FUND, L.P. SST ADVISERS, L.L.C. CLEAN DIESEL TECHNOLOGIES INC 0000949428 3564 061393453 DE 1231 SC 13D 34 005-51147 11953855 4567 TELEPHONE ROAD SUITE 206 VENTURA CA 93003 805 639 9458 4567 TELEPHONE ROAD SUITE 206 VENTURA CA 93003 MARXE AUSTIN W & GREENHOUSE DAVID M 0001044321 000000000 SC 13D C/O SPECIAL SITUATIONS FUNDS 527 MADISON AVENUE, SUITE 2600 NEW YORK NY 10022 2122076500 C/O SPECIAL SITUATIONS FUNDS 527 MADISON AVENUE, SUITE 2600 NEW YORK NY 10022 SC 13D 1 cleandiesel13dt.txt