MediaTek has announced strong sales for September, bringing its third-quarter revenues to NT$39.2 billion, the company's highest quarterly figures and higher than its guidance of NT$34.9-37.6 billion.

For September alone, revenues reached NT$13.04 billion (US$444.19 million), up 2.3% sequentially and 18.5% on year. For the first nine months of 2013, revenues amounted to NT$96.26 billion increasing 32.7% from a year earlier.

However, MediaTek expects its revenues to slide 10-15% sequentially to NT$33-35 billion in the fourth quarter due to a high base recorded in third quarter and seasonal inventory checks at clients, according to the company.

Buoyed by strong sales in September, MediaTek is also expected to see its operating margin climb higher in the third quarter from the 17.7% recorded in the previous quarter, according to an industry estimate.