OPPENHEIMER MAIN STREET CALIFORNIA MUNICIPAL FUND
Supplement dated October 27, 1997 to the
Prospectus dated November 1, 1996
The Prospectus is changed as follows:
1. The "Shareholder Transaction Expenses" table and the paragraph following
it on page 3 are replaced with the following:
Annual Fund Operating Expenses (as a Percentage of Average Net Assets):
Class A Class B
Shares Shares
- -------------------------------------------------------------------------------
Management Fees (with expense waiver) .40% .40%
- -------------------------------------------------------------------------------
12b-1 Plan Fees None 1.00%
- -------------------------------------------------------------------------------
Other Expenses .18% .20%
- -------------------------------------------------------------------------------
Total Fund Operating Expenses .58% 1.60%
The numbers in the chart above are projections of the Fund's business
expenses based on the Fund's expenses in its fiscal year ended June 30, 1996
These amounts are shown as a percentage of the average net assets of each class
of the Fund's shares for that year. Under the Investment Advisory Agreement the
Fund pays the Manager Management Fees, at the annual rate of 0.55% of net
assets. Pursuant to the Agreement, the Manager has agreed to waive a portion of
the fee when the Fund's net assets are less than $100 million dollars. The fee
rate, reflecting this waiver, is 0.40% when net assets are $75 million or more
but less than $100 million, 0.25% when net assets are $50 million or more but
less than $75 million, 0.15% when net assets are $25 million or more but less
than $50 million, and 0% when net assets are less than $25 million. The Manager
has voluntarily undertaken to continue to waive those expenses over 0.40% when
the net assets of the Fund exceed $100 million. Without that waiver the
Management Fee would have been 0.55% for each class of shares after the Fund's
total net assets exceed $100 million. The "12b-1 Distribution Plan Fees" for
Class B shares are the Distribution and Service Plan Fees (Service Plan fee of
0.25%) and
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the asset-based sales charge of 0.75%. The actual expenses for each class of
shares in future years may be more or less than the numbers in the chart,
depending on a number of factors, including the actual amount of the assets
represented by each class of shares
2. The first paragraph of the section entitled "Fees and Expenses" on page
20 is replaced with the following:
o Fees and Expenses. Under the Investment Advisory Agreement the Fund pays the
Manager monthly, at the annual rate of 0.55% of net assets. Pursuant to the
Agreement, the Manager has agreed to waive a portion of the fee when the Fund's
net assets are less than $100 million dollars. The fee rate, reflecting this
waiver, is 0.40% when net assets are $75 million or more but less than $100
million, 0.25% when net assets are $50 million or more but less than $75
million, 0.15% when net assets are $25 million or more but less than $50
million, and 0% when net assets are less than $25 million. The Manager has
voluntarily undertaken to continue to waive those expenses over 0.40% when the
net assets of the Fund exceed $100 million dollars. When asset level breakpoints
are reached, the fee applies to total net assets of the Fund, not only to assets
in excess of such breakpoint. The Fund's management fee for its fiscal years
ended June 30, 1996 and August 31, 1996 was 0.40% of average annual net assets.
October 27, 1997 PSO725.009
