The term custodian describes a set of services related to the administration of investments, whether they be in the same country or a different jurisdiction than where the client actually resides. To undertake this, custodians have several core functions. Now, one of these core functions is called safekeeping. Now, if you were to look up in the dictionary, safekeeping is a noun and is the preservation of something in a safe place. An example might be she'd put her wedding ring in her purse for safekeeping. Well, very much in line with this, investors put their assets, which might be the share certificates or any other form of notification or of the assets with their custodian bank, and their custodian keeps these on their behalf in a very safe place, whether that be a real vault with locks and near enough impossible to break into, or whether it be an electronic vault these days, now that we've moved into a dematerialized world. So in a custodian's role as a financial institution that holds customers securities for safekeeping in order to minimize the risk of their theft or loss, a custodian holds securities and other assets in electronic or physical form. Since they're responsible for the safety of the assets and securities that might be worth hundreds of millions, in fact will be worth billions, if not trillions of dollars. Custodians tend to be large and reputable firms. As you might remember from the list of major custodian organizations, the purpose of being a safe keep is to ensure that all the instruments are properly controlled and only released from safekeeping, in accordance with the authorized instructions from or on behalf of the beneficial owner. Remember, the custodian is the legal owner through the nominee relationship. However, the beneficial owner is the underlying client that instructed the custodian to buy the instrument on their behalf.