EXHIBIT 11 BOSTON BIOMEDICA, INC. AND SUBSIDIARIES STATEMENT RE COMPUTATION OF PER SHARE EARNINGS
YEAR ENDED DECEMBER 31, SIX MONTHS ENDED JUNE 30, ----------------------- ------------------------- 1993 1994 1995 1995 1996 ---- ---- ---- ---- ---- WEIGHTED AVERAGE SHARES OUTSTANDING: Average common stock outstanding 2,402,534 2,551,946 2,569,641 2,562,399 2,625,241 Net effect of dilutive common stock equivalents -- based on treasury stock method using average market price -- -- 548,542 -- 623,044 Issuance of "cheap stock" 35,191 35,191 33,297 35,191 4,358 ------ ------ ------ ------ ------ Weighted average common and common equivalent shares outstanding 2,437,725 2,587,137 3,151,477 2,597,590 3,252,643 ========= ========= ========= ========= ========= ADJUSTED NET INCOME: Income before extraordinary item 92,586 96,528 102,990 (36,156) 82,869 Extraordinary item -- gain on elimination of debt, net of income taxes 49,736 -- -- -- -- ------ ------ ------- ------ ------ Net income 142,322 96,528 102,990 (36,156) 82,869 Add: net reduction of interest on debt, less 40% taxes based on adjusted treasury stock method -- -- 27,258 -- 20,894 ------- ------ ------- ------- ------- Adjusted net income for earnings per share calculation 142,322 96,528 130,248 (36,156) 103,763 ======= ====== ======= ======= ======= Income (loss) per share 0.06 0.04 0.04 (0.01) 0.03 ==== ==== ==== ===== ==== 1993 1994 1995 1995 1996 ---- ---- ---- ---- ---- SUPPLEMENTARY EARNINGS PER SHARE DATA: (1) Weighted average common and common equivalent shares outstanding 3,151,477 3,252,643 Additional shares to retire debt 448,530 448,530 --------- --------- Pro forma shares outstanding 3,600,007 3,701,173 ========= ========= Adjusted net income for earnings per share calculation 130,248 103,763 Add: interest expense, net of tax benefit 201,539 101,081 --------- --------- Pro forma adjusted net income for earnings per share calculation 331,787 204,844 ========= ========= Pro forma income per share 0.09 0.06 ==== ==== (1) The pro forma income per share assumes the Offering issues only shares sufficient to retire all outstanding debt as of January 1, 1995, thereby causing interest expense to be added back to net income, net of tax benefits using a 40% combined federal and state tax rate.