Norton AntiVirus, developed and distributed by Symantec Corporation, provides malware prevention and removal during a subscription period. It uses signatures and heuristics to identify viruses. Other features include e-mail spam filtering and phishing protection. Symantec distributes the product as a download, a box copy, and as OEM software. Norton AntiVirus and Norton Internet Security, a related product, held a 61% US retail market share for security suites as of the first half of 2007. Competitors, in terms of market share in this study, include antivirus products from CA, Trend Micro, and Kaspersky Lab. Norton AntiVirus runs on Microsoft Windows and Mac OS X. Windows 7 support is in development for versions 2006 through 2008. Version 2009 has Windows 7 supported update already. Versions 2010, 2011, and 2012 all natively support Windows 7, without needing an update. Version 12 is the only version fully compatible with Mac OS X Lion. In May 1989, Symantec launched Symantec Antivirus for the Macintosh (SAM). SAM 2.0, released March 1990, incorporated technology allowing users to easily update SAM to intercept and eliminate new viruses, including many that didn't exist at the time of the program's release. In August 1990 Symantec acquired Peter Norton Computing from Peter Norton. Norton and his company developed various DOS utilities including the Norton Utilities, which did not include antivirus features. Symantec continued the development of acquired technologies. The technologies are marketed under the name of "Norton", with the tagline "from Symantec". Norton's crossed-arm pose, a registered U.S. trademark, was traditionally featured on Norton product packaging. However, his pose was later moved to the spine of the packaging, and eventually dropped altogether. By early 1991, U.S. computers were invaded by hundreds of foreign virus strains and corporate PC infection was becoming a serious problem. Symantec's Norton Group launched Norton AntiVirus 1.0 (NAV) for PC and compatible computers. Ads for the product, with suggested retail $129, featured Norton in his crossed-arm pose, wearing a pink shirt and surgical mask covering his nose and mouth. With the 1999 - 2001 version 5.0 updated by an elite team (Tim Grant - MIT, S(Saikat) Nick Barua - Rice University and Robert Thomas - MIT) , SAM was renamed Norton AntiVirus (NAV) for Macintosh.