The 25-year-old controversially walked out on Bradford Bulls at the end of the season, but following an investigation from the RFL, Kopczak has been allowed to sign for the Giants.
“Huddersfield have been top-four material for the past few years and the chance to work with Paul Anderson for me as a fellow prop was too good to miss out on,” Kopczak told the Giants’ site.
“I have been fed up reading many of the comments attributed to my decision to simply look after my family’s best interest and we are all happy that this is now behind us and we can move forward in a Giants shirt next season.
“I went through the squad yesterday with my manager and it’s going to be an exciting year for the Giants with lots of new signings in there and definitely lots of size.
“I see no reason at all why we can’t be challenging at the very top and for me I want a massive year to lead into the World Cup.”
The Giants have already signed experienced forwards Stuart Fielden from Wigan and Ukuma Ta’ai, who made the switch from New Zealand Warriors in September.
“He is a player I have watched closely for a number of years and he has gone from a promising youngster to a top line performer and the sort of no-nonsense go-forward character that I want to see in our forward line next year,” added Anderson.
“He is a very big strong man and for a player of his age to have already made over 120 Super League appearances and plenty of internationals shows that he has always performed well for his teams in the past.”
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