Gaff has signed an extension with the Eagles that will see him don the royal blue and gold for another four seasons, while Kennedy and Hurn have both inked one-year deals.
The veteran pair joined the league via the 2005 draft, with Kennedy selected with the 4th overall selection – tied to Carlton – and Hurn taken with the 13th pick in the draft.
Kennedy was part of one of the biggest trade deals from the past 20 years, arriving to the Eagles from the Blues in exchange for Chris Judd.
The key forward has since played in 238 games for West Coast and has booted 634 goals.
Hurn’s extension places him in contention to reach the 300-game mark, with just 14 matches to go in order to reach the feat.
Gaff is set to become a one-club player after singing a four-year deal, with the 28-year-old touted as one of the favourites to win the John Worsfold Medal for 2020.