In certain cases where you have repaid some installments of a previous student loan independently, you would be given the authority of branching away the Co-borrower. This is known as Co-Borrower Release and by doing so, you ensure that the loan repayment is entirely yours. This also puts you in a position where you are not hit by the Credit History of your Co-Borrower. Both of you are separate entities speaking from the loan perspective and you would hence need to take charge of repaying your loan off.
These are just a couple of reasons why people need the money. The most common financial resource for these common problems is to get a loan. Anytime you are considering getting a loan from a financial or lending institution, it is imperative that you must sign a loan agreement.
"Investment banks" create loan agreements that cater to the needs of the investors whose funds they attempt to attract; "investors" are always sophisticated and accredited organizations not subject to bank regulatory supervision and the need to cater to the public trust. Investment banking activities are supervised by the SEC and their main focus is on whether the correct or proper disclosures are made to the parties who provide the funds.
If you have any queries in future, then you should be able to easily contact the lender. For this purpose, you should ensure that the company name, corresponding address and the phone number are mentioned in the loan agreement than the details about the agent who has been processing the loan for you.