Impinj, Inc. announced the closing of its initial public offering of 5,520,000 shares of common stock at a price to the public of $14.00 per share, which includes the full exercise of the underwriters’ option to purchase 720,000 additional shares.   The company estimates net proceeds from the offering to be approximately $69.2 million, after deducting underwriting discounts and commissions and estimated offering expenses. The shares began trading on the NASDAQ Global Select Market under the ti...