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EXHIBIT 12.1
REDBACK NETWORKS INC.
Computation of Ratio of Earnings to Fixed Charges
Pursuant to Item 503
Regulation S-K
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PERIOD FROM
AUGUST 30,
1996
(INCEPTION) THREE MONTHS ENDED
THROUGH YEAR ENDED DECEMBER 31, MARCH 31,
DECEMBER 31, --------------------------------- -----------------------
1996 1997 1998 1999 1999 2000
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(DOLLARS IN THOUSANDS)
<S> <C> <C> <C> <C> <C> <C>
Net loss............................ $ (142) $ (4,411) $ (9,876) $ (7,919) $ (3,801) $ (85,237)
Interest............................ -- 60 223 319 22 279
Amortization of interest expense
related to warrants issued......... -- 25 28 28 7 7
Lease rental expense representative
of interest (1).................... -- 48 147 414 28 196
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Net loss before fixed charges....... (142) (4,278) (9,478) (7,158) (3,744) (84,755)
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Less: fixed charges
Interest............................ -- 60 223 319 22 279
Amortization of interest expense
related to warrants issued....... -- 25 28 28 7 7
Lease rental expense representative
of interest (1).................. -- 48 147 414 28 196
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Total fixed charges................. -- 133 398 761 57 482
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Net loss............................ $ (142) $ (4,411) $ (9,876) $ (7,919) $ (3,801) $ (85,237)
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Ratio of earnings to fixed charges.. N/A N/A N/A N/A N/A N/A
Deficiency in earnings.............. (2) $ (4,411) $ (9,876) $ (7,919) $ (3,801) $ (85,237)
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(1) Calculated as one-third of rentals, which is a reasonable approximation of
the interest factor.
(2) Redback had no fixed charges in the period from inception (August 30, 1996)
through December 31, 1996.
