Sycamore Networks (SCMR)

Provision for Income Taxes

The provision for income taxes of $0.1 million for fiscal 2005 was recorded for taxes due on income generated in foreign tax jurisdictions and certain states. We did not record any net tax benefits relating to our net losses due to the uncertainty surrounding the realization of these future tax benefits.

Provision for Income Taxes

We did not provide for income taxes for fiscal 2004 or fiscal 2003 due to our cumulative taxable losses in recent years and the net losses incurred during each period. We did not record any tax benefits relating to these losses due to the uncertainty surrounding the realization of these future tax benefits.

Provision for Income Taxes

We did not provide for income taxes for the three and nine months ended April 30, 2005, or for the same periods in fiscal 2004, due to our cumulative tax losses in recent years and the net losses incurred during each period. We did not record any tax benefits relating to these losses due to the uncertainty surrounding the realization of these deferred tax assets. Under the provisions of the Internal Revenue Code of 1986, as amended, if certain substantial changes in our ownership were to occur, we could be limited in the future in the amount of net operating losses and other tax attributes that could be utilized annually to offset future taxable income. Future tax benefits have not been recognized in the financial statements, as their utilization is considered uncertain based on the weight of available information.

Provision for Income Taxes

We did not provide for income taxes for the first quarter of fiscal 2004, or the first quarter of fiscal 2003, due to our cumulative taxable losses in recent years and the net losses incurred during each period. We did not record any tax benefits relating to these losses due to the uncertainty surrounding the realization of these deferred tax assets.

Provision for Income Taxes

We did not provide for income taxes for the three and six months ended January 29, 2005, or for the same periods in fiscal 2004, due to our cumulative tax losses in recent years and the net losses incurred during each period. We did not record any tax benefits relating to these losses due to the uncertainty surrounding the realization of these deferred tax assets. Under the provisions of the Internal Revenue Code of 1986, as amended, if certain substantial changes in our ownership were to occur, we could be limited in the future in the amount of net operating losses and other tax attributes that could be utilized annually to offset future taxable income. Future tax benefits have not been recognized in the financial statements, as their utilization is considered uncertain based on the weight of available information.

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Provision for Income Taxes

We did not provide for income taxes for fiscal 2003 or fiscal 2002 due to our cumulative taxable losses in recent years and the net losses incurred during each period. We did not record any tax benefits relating to these losses due to the uncertainty surrounding the realization of our deferred tax assets.

Provision for Income Taxes

We did not provide for income taxes for the three and six months ended January 29, 2005, or for the same periods in fiscal 2004, due to our cumulative tax losses in recent years and the net losses incurred during each period. We did not record any tax benefits relating to these losses due to the uncertainty surrounding the realization of these deferred tax assets. Under the provisions of the Internal Revenue Code of 1986, as amended, if certain substantial changes in our ownership were to occur, we could be limited in the future in the amount of net operating losses and other tax attributes that could be utilized annually to offset future taxable income. Future tax benefits have not been recognized in the financial statements, as their utilization is considered uncertain based on the weight of available information.