These are the ones I’m aware of:
-ms-Microsoftmso-Microsoft Office-moz-Mozilla Foundation (Gecko-based browsers)-o-,-xv-Opera Software-atsc-Advanced Television Standards Committee-wap-The WAP Forum-webkit-Safari, Chrome (and other WebKit-based browsers)-khtml-,-konq-Konqueror browser-apple-Webkit supports properties using the -apple- prefixes as wellprince-YesLogic-ah-Antenna House-hp-Hewlett Packard-ro-Real Objects-rim-Research In Motion-tc-Tall Components
These are officially listed in the CSS 2.1 Specification, informative section 4.1.2.2.