New factories were built, first in 1970 to increase production of upright pianos, and then in 1989 a second plant to concentrate on the grand piano market. By 1990 serial numbers had reached 450,000.

Petrof currently produces  around 12,000 uprights and 1,750 pianos a year, and employs 1,000 people. Tovarna na piano, established in 1997, united with Petrof  in 2001, marking the climax of a privatization process that began in 1991.

Dates and serial numbers when the pianos were manufactured