X0304 4 2012-02-21 0 0000726514 ELECTRO SCIENTIFIC INDUSTRIES INC ESIO 0001282683 Nierenberg Investment Management Company, Inc. 19605 NE 8TH STREET CAMAS WA 98607 1 0 1 0 0001040899 Nierenberg David 19605 NE 8TH STREET CAMAS WA 98607 0 0 1 0 0001365745 D3 Family Bulldog Fund, LP 19605 NE 8TH STREET CAMAS WA 98607 0 0 1 0 0001405824 D3 Family Canadian Fund, LP 19605 NE 8TH STREET CAMAS WA 98607 0 0 1 0 0001282684 DIII Offshore Fund, LP 19605 NE 8TH STREET CAMAS WA 98607 0 0 1 0 0001365764 Nierenberg Investment Management Offshore Inc. 19605 NE 8TH STREET CAMAS WA 98607 0 0 1 0 Common Stock 2012-02-21 4 S 0 7770 15.1 D 2302066 I By The D3 Family Bulldog Fund, LP Common Stock 2012-02-21 4 S 0 650 15.1 D 191478 I By The D3 Family Canadian Fund, LP Common Stock 2012-02-21 4 S 0 1427 15.1 D 423715 I By the DIII Offshore Fund, LP Common Stock 2012-02-22 4 S 0 26130 15.0 D 2275936 I By The D3 Family Bulldog Fund, LP Common Stock 2012-02-22 4 S 0 2170 15.0 D 189308 I By The D3 Family Canadian Fund, LP Common Stock 2012-02-22 4 S 0 4806 15.0 D 418909 I By the DIII Offshore Fund, LP Common Stock 2012-02-23 4 S 0 8595 15.0 D 2267341 I By The D3 Family Bulldog Fund, LP Common Stock 2012-02-23 4 S 0 715 15.0 D 188593 I By The D3 Family Canadian Fund, LP Common Stock 2012-02-23 4 S 0 1581 15.0 D 417328 I By the DIII Offshore Fund, LP Common Stock 573129 I By The D3 Family Fund, LP Each of the reporting persons disclaims beneficial ownership of these securities except to the extent of the reporting person's pecuniary interest therein. David Nierenberg 2012-02-23 David Nierenberg, President, Nierenberg Investment Management Company, Inc. (NIMCO) 2012-02-23 David Nierenberg, President, NIMCO, General Partner of The D3 Family Canadian Fund, LP 2012-02-23 David Nierenberg, President, NIMCO, General Partner of The D3 Family Bulldog Fund, LP 2012-02-23 David Nierenberg, President, NIMO, General Partner of The DIII Offshore Fund, LP 2012-02-23 David Nierenberg, President, Nierenberg Investment Management Offshore, Inc. (NIMO 2012-02-23