Proto Labs (NYSE:PRLB - Get Free Report) issued its earnings results on Friday. The industrial products company reported $0.54 earnings per share for the quarter, beating analysts' consensus estimates of $0.40 by $0.14. Proto Labs had a net margin of 3.98% and a return on equity of 3.19%. The firm had revenue of $139.34 million for the quarter, compared to analyst estimates of $135.31 million. During the same quarter last year, the business post…