Mocon Inc., a Minneapolis maker of laboratory instruments for research and quality control, Wednesday reported a 67 percent drop in third-quarter earnings to $493,000, or 9 cents a share.

A 30 percent increase in revenue, to $12.3 million, was largely due to the April acquisition of PBI-Dansensor A/S that added $4.2 million to sales, the company said.

The company said its gross profit margin was hurt by lower product sales and the costs related to the acquisition.

After the earnings announcement, Mocon stock fell 4 cents a share, or 0.2 percent, to close at $14.91.