The current institutional shareholding score of Proto Labs Inc is 10.00, ranking 1 out of 182 in the Machinery, Tools, Heavy Vehicles, Trains & Ships industry. The latest institutional shareholding proportion is 105.04%, representing a quarter-over-quarter increase of 11.54%. The largest institutional shareholder is James Simons, holding a total of 0.00 shares, representing 2.19% of shares outstanding, with 0.16% increase in holdings.