IBM was the first company to launch mini computers
There are arguments even now as to the first minicomputer. If we consider a minicomputer to be a single cabinet machine, capable of mass data processing and supporting a number of terminals then probably the PDP8 from 1964 fits the bill. This was made by Digital Equipment company in the US.
1971_developers of the 1st mini computer
(Ching-Chun Hsieh、Jong-Chuang Tsay、Sin-Min Tsai)
The term "minicomputer" developed in the 1960s to describe the smaller computers. A mini computer is not an invention it is called a modified version of a larger computer.