Aside from verbal, consensual and real contracts there were also literal contracts in the Roman law, which means they were made in writing. Despite few sources we know that they were quite diverse. Due to their nature it was easy to use them as evidence. They were valued for their precision and the clarity with which they stated the obligations and they could refer to both the citizens as well as the peregrines, depending on which specific type of contract was used.
Expensilatio was a literal contract which originated from ius civile and hence was related to the citizens. It was derived from the records in the Roman accounting books which were kept in every roman house (codex accepti et expensi). All the expenses as well as income was recorded and such a record had a legal force. If there was an obligation created, then its subject was in the form of a specifically stated sum of money but not every record resulted in creating an obligation because part of the records which concerned old obligations and stated the base for the obligations (nomina arcaria) could be used solely as evidence. Obligations were created when a debt claim was recorded (nomen transcripticium) which means recording a debt sum in the creditor’s book with the consent of the debtor and they were of abstract nature.
There were two types of nomina transcripta. Transcriptio a re in personam was created with mutual consent between the parties which were already bound by an obligation of a different type in order to change that obligation into a literal contract. The other type was transcriptio a persona in personam which was used in order to change the debtor by crossing out the original debt and entering a new one, referring to a different person, in its place.
Also the peregrines could use the literal contracts. They used contracts originating from z ius gentium which were called chirographa and syngrapha, written personally by the debtor. The names themselves prove the Greek origin of these contracts. These types of contracts appeared in Rome in the 1st century BCE. The difference between the two types was the number of copies which were created – in the case of chirographa there was only one copy while syngrapha were created in two copied, one for each party, and was signed by both the creditor and the debtor.
Literal contracts gradually faded from use since the Romans preferred oral obligations. In the imperial period expensilatio disappeared completely (end of 3rd century CE). The written contracts came back only in the subsequent centuries under the Hellenic influences and developed so far that the creation of a written document became a requirement for the validity of a legal act.