Vencill launched a lawsuit against the company in 2003 after his urine tested positive for 19-norandrosterone at 4 ng/mL, a substance that is restricted for high-level swimmers, resulting in a two-year ban from swimming competitions, including the Olympic trials.
Vencill claimed that the substance originated from contamination of Ultimate Nutrition's multivitamin product, Super Complete.
In May, a civil jury found in favor of Vencill, awarding him $578,000 in damages.
Independent testing reportedly showed that the multivitamin had been contaminated.
But the company says that multiple tests carried out at the University of Southern California on capsules from the same lot number as those purportedly taken by Vencill, from preceding and following lot numbers and, indeed, from the very same bottle from which Vencill allegedly consumed capsules all showed up negative for contaminants.
It has also said that all its non-prohormone products, including Super Complete, are manufactured at facilities that do not make prohormones, steroid precursors, or steroid metabolites. Nor does the company source ingredients from suppliers that manufacture these substances.
According to Ultimate Nutrition's attorney Todd Croutch, a "mutually agreeable" resolution has been reached between Vencill and Ultimate Nutrition.