Online marketing and media services company QuinStreet plans to go public with the sale of about $250 million in common stock, it revealed in a regulatory filing late last week.

Founded in 1999, the company presently employs about 500 employees. Its clients include ADT home security systems and DeVry University, along with various dating sites, video game publishers and credit-card companies.

Credit Suisse Securities LLC, Bank of America Merrill Lynch, and J.P. Morgan Securities Inc. are managing and underwriting the offering, according to QuinStreet, while Qatalyst Partners is acting as a financial advisor.

Without revealing how many shares it plans to offer or at what price range, QuinStreet said in its filing with the Securities and Exchange Commission that it expects to trade using the ticker symbol "QNST."

For the fiscal year that ended June 30, QuinStreet said it generated revenue of $261 million -- up 36% year-over-year -- and earnings before interest, taxes, depreciation and amortization, or EBITDA, of $57 million -- up 57%.

While it didn't disclose its profits, Chief Financial Officer Ken Hahn told The Wall Street Journal at the time that QuinStreet's net income was $19 million for the year, and that it has been profitable since 2002.

QuinStreet is backed by about $60 million in venture funding from Minneapolis-based Split Rock Partners, Sutter Hill Ventures, Granite Global Ventures, and Catterton Partners, among other investors.

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