Stock buyback plans are often used on Wall Street to shore up the price of ailing stocks or bump strong ones even higher. By decreasing the number of shares available, the theory goes, the stock price will go up. It often works. Grayscale’s shares have been ailing recently, as Canada approved a pair of Bitcoin exchange traded funds—the first in North America. The first ETF, Purpose Bitcoin ETF, roared to life with more than $500 million invested in just the first few days.