X0202 4 2005-03-14 0 0001115143 ACUSPHERE INC ACUS 0001080163 WEISEL THOMAS PARTNERS GROUP LLC/CA ONE MONTGOMERY STREET SUITE 3700 SAN FRANCISCO CA 94104 0 0 1 0 0001265425 WEISEL THOMAS CAPITAL PARTNERS LP 390 PARK AVENUE 17TH FLOOR NEW YORK NY 10022 0 0 1 0 0001094251 TWP CEO FOUNDERS CIRCLE QP LP 390 PARK AVENUE 17TH FLOOR NEW YORK NY 10022 0 0 1 0 0001265423 WEISEL THOMAS CAPITAL PARTNERS DUTCH LP 390 PARK AVENUE 17TH FLOOR NEW YORK NY 10022 0 0 1 0 0001265421 WEISEL THOMAS CAPITAL PARTNERS DUTCH II LP 390 PARK AVENUE 17TH FLOOR NEW YORK NY 10022 0 0 1 0 0001265418 TWP 2000 CO INVESTMENT FUND LP ONE MONTGOMERY STREET SUITE 3700 SAN FRANCISCO CA 94104 0 0 1 0 0001094252 TWP CEO FOUNDERS CIRCLE AI LP 390 PARK AVENUE 17TH FLOOR NEW YORK NY 10022 0 0 1 0 0001090397 WEISEL THOMAS CAPITAL PARTNERS EMPLOYEE FUND LP 390 PARK AVENUE 17TH FLOOR NEW YORK NY 10022 0 0 1 0 0001313811 TAILWIND CAPITAL PARTNERS LLC 390 PARK AVENUE 17TH FLOOR NEW YORK NY 10022 0 0 1 0 Common Stock 2005-03-14 4 S 0 10000 5.50 D 2234098 I See Footnote 2 The amount reported in Table 1, Column 4 includes 8,573 shares which were disposed of by Thomas Weisel Capital Partners, L.P., 724 shares which were disposed of by TWP CEO Founders' Circle (QP), L.P., 198 shares which were disposed of by TWP CEO Founders' Circle (AI), L.P., 201 shares which were disposed of by Thomas Weisel Capital Partners (Dutch), L.P., 201 shares which were disposed of by Thomas Weisel Capital Partners (Dutch II), L.P., 63 shares which were disposed of by Thomas Weisel Capital Partners Employee Fund, L.P. and 40 shares which were disposed of by TWP 2000 Co-Investment Fund, L.P. Thomas Weisel Partners Group LLC is the managing member of an entity that is (i) the managing member of Tailwind Capital Partners LLC and (ii) the general partner of TWP 2000 Co-Investment Fund, L.P., and thus may be deemed to beneficially own the shares beneficially owned by these entities. Tailwind Capital Partners LLC is (i) the general partner of Thomas Weisel Capital Partners, L.P., TWP CEO Founders' Circle (AI), L.P., TWP CEO Founders' Circle (QP), L.P. and Thomas Weisel Capital Partners Employee Fund, L.P. and (ii) the managing member of the general partner of Thomas Weisel Capital Partners (Dutch), L.P. and Thomas Weisel Capital Partners (Dutch II), L.P., and thus may be deemed to beneficially own the shares held by these entities. The reporting persons disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein. See signatures included in Exhibit 99.1 2005-03-16