ThunderBYTE Anti-Virus (TBAV) was an early antivirus software product.
It was created by Dutchman Frans Veldman in 1988, and published by his company, ESaSS B.V.
Originally ThunderBYTE used a dedicated ISA card to provide protection before the operating system was even loaded.
Later, a software-only product was released, which soon displaced the hardware offering.
In 1998, TBAV was sold to Norman ASA,[1] which discontinued ThunderBYTE as a product.