Ironic isn't it? The most useful service and (... no seeds, no stems, no sticks))) nobody knows nothing about the way they operate. They gotta use something to generate BTC wallet addresses for the registered users aren't they?
Thats not ironic because there must be a tangible reason why their boards choose to kept the information hidden and the last time i checked coinbase is not the only centralized exchanve site that dont expose the derivation path they used but I'm that they will use either the BIP39 or 44.