"We have a long-standing policy that prohibits coaches from any relationship with a supplement company," league spokesman Brian McCarthy wrote Wednesday in an e-mail to The Associated Press. "Coach Jackson is now in compliance."
The policy applies to coaches only, not players, McCarthy wrote.
ThePostGame.com first reported Wednesday that the league ordered Jackson to cut ties with Sports With Alternatives To Steroids (SWATS). The website also reported that SWATS markets a product the supplement company says contains a byproduct of human growth hormone that is banned by the NFL.
McCarthy wrote to The AP that Jackson needed to separate himself from the SWATS because it is a supplement company, not because of any particular product.
According to ThePostGame.com, Jackson began endorsing the company when he was an assistant with the Baltimore Ravens from 2008 to 2009. He told the website he is no longer affiliated with the company.
Jackson was introduced Tuesday as the Raiders' coach after one season as their offensive coordinator.
Copyright 2011 by The Associated Press