Korva Class Destroyer was originally designed to serve exclusively the House of Korva, during the Klingon civil war and later was used in the war agains the Dominion. Eventually, the schematics were released to the Klingon shipyards where a small fleet was constructed to serve the empire.
Vokull Class Destroyer was originally designed to serve the House of Vokull. Only one prototype was ever made, but it was made of such stern material that only one was all the house ever needed. The Vokul engaged and destroyed several Cardassian, Jem Hadar and the occasional Ferengi vessel in its years of service to House Vokull.