Bacterin International Holdings, Inc. provided preliminary unaudited revenue guidance for the fourth quarter of 2013. The company is expecting total net revenues for the fourth quarter of 2013 to be in the range of $8.15 million to $8.28 million, representing a sequential increase of approximately 4% over the third quarter 2013, and an increase of 1.5% when compared to $8.1 million for the fourth quarter 2012. The company is anticipating Biologics revenue to be in the range of $8.02 million to $8.07 million for the quarter, a 5.0% increase over the third quarter 2013, and 4.5% increase year-over-year.