Coinbase is a legit company. Coinbase is registered as a Money Service Business (MSB) allowing financial institutions to conduct transactions with it. The corporate office in San Francisco has uniformed security officers as soon as you enter. Yes, Coinbase is a legitimate company operating in 47 states. (GDAX not allowed In Wyoming, Minnesota, and Hawaii).
With all that said, there are many, many risks trusting a third-party to hold your private keys or recovery phrases. Especially exchanges. I won’t list them all but just last week, $170 million worth of the cryptocurrency Nano (17 million tokens) got hacked/stolen from the licensed Italian cryptocurrency exchange Bitgrail. Don’t take the risk trusting a third party exchange to store your value. Especially if you have serious coin in this space. Don’t think it can’t/won’t happen to you.
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