Summit Partners has invested $100m growth capital for a minority stake in Czech software vendor avast!

vast! offers free antivirus software as a complete computer security application. The software is estimated to protect about 100 million computers globally, primarily from malware.

The avast! software was first developed by the company's co-founders Eduard Kucera and Pavel Baudis, who wrote a programme to remove the Vienna virus in 1988. The duo then moved on to launch avast! as a free antivirus in 2000.