Investors who bought shares in GoPro after it went public in June are questioning the release by J.P. Morgan of 5.82 million shares from a lock-up restriction. The shares have been gifted by the action camera maker's founders, Nicholas and Jill Woodmann, to a charitable foundation with effect from Oct. 3. It was not clear at the time of going to press if and when the foundation had any plans to sell the shares. The news sent the price of the stock down by almost 14 percent to $79.13, but then it went back to around $90, more than three times the $24 price of the initial public offering.