The Peter Norton group merger logistical effort began immediately while the companies sought approval for the merger, and in August 1990, Symantec concluded the purchase—by this time the combination of the companies was already complete. Symantec's consumer antivirus and data management utilities are still marketed under the Norton name. At the time of the merger, Symantec had built upon its Turner Hall Publishing presence in the utility market, by introducing Symantec Antivirus for the Macintosh (SAM), and Symantec Utilities for the Macintosh (SUM). These two products were already market leaders on the Mac, and this success made the Norton merger more strategic. Symantec had already begun the development of a DOS-based antivirus program one year before the merger with Norton. The management team had decided to enter the antivirus market in part because it was felt that the antivirus market entailed a great deal of ongoing work to stay ahead of new viruses. The team felt that Microsoft would be unlikely to find this effort attractive, which would lengthen the viability of the market for Symantec. Turner decided to use the Norton name for obvious reasons, on what became the "Norton Antivirus", which Turner and the Norton team launched in 1991. At the time of the merger, Norton revenues were approximately 20 to 25% of the combined entity. By 1993, while being led by Turner, Norton product group revenues had grown to be approximately 82% of Symantec's total.