On the FedEx US Airbills we have at the office, there are three delivery signature options: no signature required, direct signature, and indirect signature. None required is self-explanatory. Direct means that anyone at the recipient’s address can sign for the package. Indirect means that anyone at a neighboring address can sign. There is, however, no option for “only delivered if the recipient signs.”

Which isn’t critical, by any stretch — or even usually an issue — but I do find it a little weird that the option isn’t even there.