The Mark XII Sentinel Droid was a deriative of the venerable Sentinel-droid series of Jedi Civil War fame. Secretly revived in 16 ABY, they began production in 17 ABY under the aegis of the Outer Rim Manufacturing company, all production secretly being diverted to the Sith Covenant. After the formation of the Sith Enclave, production rights passed to Madilim IronWorks, who began producing the droid for the Sith Enclave.