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March 18 (Reuters) - Monster Worldwide Inc (MNST.O) said it expects first-quarter total operating expenses, excluding certain costs, to exceed consensus estimates, citing a "disproportionate amount" of marketing costs.
Shares of Monster Worldwide, parent of Internet jobs site Monster.com, fell 9 percent to $23.35 in after-hours trading. They had closed up almost 7 percent at $25.70 Tuesday on Nasdaq.
The company expects first-quarter non-GAAP operating expenses of $327 million to $333 million, which include costs related to branding initiatives and workforce compensation.
Market estimates for Monster's first-quarter operating expenses could not immediately be verified.
These expenses have been partially offset by benefits from the company's ongoing restructuring program, the company said.
"The timing of our investments and cost reduction initiatives happen at irregular intervals and may impact short-term results," Chief Executive Sal Iannuzzi said.
Monster said it expects a return to more normal marketing expense levels in future periods.
The company also said it is on track with the workforce cuts outlined in its restructuring plan.
Monster will continue its policy of not providing outlook for 2008, it said. (Reporting by Purwa Naveen Raman in Bangalore; Editing by Pratish Narayanan)