There is a fee of $435 assessed for the first document filed in a civil action including in the case of a marital dissolution. That first document could be your petition for dissolution or your response to a petition that was served on you. For a list of all fees for the Superior Court for the State of California, County of Los Angeles go to this link: http://www.lasuperiorcourt.org/feesnet/pdf/fee-schedule-2012.pdf
The filing fee varies a bit, depending on your county. For example, in L.A., it's $435 but in San Francisco, it's $450. You can find the filing fees for your county on the county specific superior court website.
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