The BBC reports that Sharapova, who admitted in March that she had tested positive for meldonium, a heart disease drug which has been a banned substance since 1 January 2016, is appealing the ban.
Nike had initially suspended its relationship with her, saying it would monitor the investigation.
In a statement following yesterday's decision Nike said: "The ITF Tribunal has found that Maria did not intentionally break its rules."
"Maria has always made her position clear, has apologised for her mistake and is now appealing the length of the ban.
"Based on the decision of the ITF and their factual findings, we hope to see Maria back on court and will continue to partner with her."
Head's chairman Johan Eliasch said: "We believe, based on the facts and circumstances provided to us, that this is a flawed decision. HEAD will continue to stand by Miss Sharapova."