Coinbase Global has been searching for new ways to make money. One business it flirted with was controversial: using its own money to speculate on cryptocurrencies. WSJ: Last year, Coinbase — which operates a large cryptocurrency exchange that handles bitcoin and other digital coins — hired at least four senior Wall Street traders and launched a group to generate profit, in part, by using the company’s cash to trade and “stake,” or lock up, cryptocurrencies, according to people close to the matter. The activity was described as “proprietary” trading by the people at the company. Earlier this year, the team completed a $100 million transaction that the group viewed as a test trade of the new effort, according to the people. The transaction came after Coinbase executives testified to members of Congress last year that the company didn’t buy and sell digital currencies for its own account. The monthslong effort to launch the Coinbase Risk Solutions group underscores how Coinbase, which has seen its shares tumble about 70% over the past year, has entertained more aggressive strategies as it tries to develop new businesses. Coinbase says some at the company examined pursuing proprietary trading but decided against it.