EXHIBIT 12 3M Company and Subsidiaries CALCULATION OF THE RATIO OF EARNINGS TO FIXED CHARGES (Unaudited)

- -------------------------------------------------------------------------- Nine Months Ended Sep. 30, Year Year Year Year Year (Dollars in millions) 2003 2002 2001 2000 1999 1998 - -------------------------------------------------------------------------- EARNINGS Income from continuing operations before income taxes, minority interest, extraordinary loss and cumulative effect of accounting change* $2,719 $3,005 $2,186 $2,974 $2,880 $1,952 Add: Interest expense 83 100 143 127 125 139 Interest component of the ESOP benefit expense 10 16 18 19 21 29 Portion of rent under operating leases representative of the interest component 33 40 39 39 37 41 Less: Equity in undistributed income of 20-50% owned companies 6 10 5 10 4 4 - --------------------------------------------------------------------------- TOTAL EARNINGS AVAILABLE FOR FIXED CHARGES $2,839 $3,151 $2,381 $3,149 $3,059 $2,157 - --------------------------------------------------------------------------- FIXED CHARGES Interest on debt 76 100 150 141 135 139 Interest component of the ESOP benefit expense 10 16 18 19 21 29 Portion of rent under operating leases representative of the interest component 33 40 39 39 37 41 - --------------------------------------------------------------------------- TOTAL FIXED CHARGES $ 119 $ 156 $ 207 $ 199 $ 193 $ 209 - --------------------------------------------------------------------------- RATIO OF EARNINGS TO FIXED CHARGES 23.9 20.2 11.5 15.8 15.8 10.3 - --------------------------------------------------------------------------- *Nine months ended September 30, 2003, includes a $93 million pre-tax loss related to an adverse ruling associated with a lawsuit filed by LePage's Inc. Year 2002 and year 2001 special items include net pre-tax losses of $202 million and $504 million, respectively, primarily related to the restructuring; 2000 includes net pre-tax losses of $23 million related to special items; 1999 includes net pre-tax gains of $100 million relating to special items that include gains on divestitures, litigation expense, an investment valuation adjustment, and a change in estimate that reduced 1998 restructuring charges; 1998 includes pre-tax restructuring charges of $493 million.