For the third quarter ended September 30th, 2010, we recorded revenue of $9.3 million compared to $9.7 million in the second quarter. Our gross margin for the third quarter was 40.1% compared to 39.6% for the second quarter. As noted, we were pleased our gross margins benefited from a product mix shift to advanced products, higher ASPs, and favorable unit cost as a result of enhanced processing technology, as well as improved product design.
For the third quarter, total stock-based compensation expense amounted to a credit of $0.2 million, after a true-up of underestimated forfeiture rate compared to an expense of $0.9 million in the second quarter.
R&D expense was $3.9 million or 42% of revenue for the third quarter, which was slightly lower than the second quarter of $4.4 million, due to the reversal of overestimated stock-based compensation expense. With the addition of approximately 40 engineers from Mavrix, which we acquired this quarter, we anticipate our R&D expense to continue to represent a high percentage of revenue as we focus on our product development initiatives.
G&A expense was $1.8 million in the third quarter or 19.7% of revenue, which was slightly lower than the second quarter of $2.4 million, also due to the true-up of employee forfeiture rate on our stock-based compensation expense.Sales and marketing expense was $0.2 million in the third quarter or 2.5% of revenue compared to $0.3 million in the second quarter. We continue to tightly manage expense levels in this category, as a demonstrated by our hiring freeze across non-engineering functions and the salary cuts at the management level. Operating loss was $1.8 million for the third quarter compared to operating loss of $2.9 million for the second quarter. We continue to focus on the sequential improvement in profitability and our persistent cost management in the third quarter.