The Computer Assisted Trading System (CATS) was developed by the Toronto Stock Exchange in 1977 and implemented in the Madrid Stock Exchange (MSE) in 1989. This was the world's first fully electronic trading system. The MSE initially traded seven large-cap stocks on the system and expanded to 51 by the end of the year.






Taobiz explains Madrid SE CATS (MSE) .MC
By 1995, the Madrid Stock Exchange had replaced CATS with the Sistema de Interconexión Bursátil Español (SIBE), a more modern electronic trading system developed by the MSE. SIBE connects the four Spanish stock exchanges (Madrid, Valencia, Bilbao and Barcelona) to form a unified, continuous market, providing price information and other data in real time.