Benzinga's Top Pre-Market Losers

F5 Networks Inc FFIV dipped 2.19% to $116.05 in the pre-market session. FFIV is all set to report its quarterly earnings today. Yahoo! Inc YHOO dropped 1.78% to $14.33 in the pre-market trading. Yahoo's search revenue dropped 45% year-over-year to $467 million. St. Jude Medical Inc STJ moved down 1.75% to $46.00 in the pre-market session. STJ issued downbeat earnings forecast. Ecolab Inc ECL fell 1.61% to $54.50 in the pre-market session. Ecolab announced its plans to buy Nalco Holding Co NLC for around $5.4 billion.