The 23-year-old defenseman, who was selected by Vancouver with the No. 5 pick in the 2016 NHL Draft, scored three points (two goals, one assist) in 23 games last season, his first in the NHL.
"We are excited to welcome another young defenseman like Olli to our organization," Panthers general manager Bill Zito said. "We look forward to Olli developing with our club as he joins our deepening core on the blue line."
Lammikko, a 25-year-old center, scored five points (four goals, one assist) in 44 games last season. Selected by Florida in the third round (No. 65) of the 2014 NHL Draft, Lammikko has scored 11 points (four goals, seven assists) in 84 games.
Juulsen, a 24-year-old defenseman, was placed on waivers by the Panthers on Oct. 1 after he played four games last season, his first in Florida. A first-round pick (No. 26) by the Montreal Canadiens in the 2015 NHL Draft, Juulsen has scored eight points (two goals, six assists) in 48 games.
"[Lammikko is] versatile," Canucks GM Jim Benning said Monday. "He can play center or the wing, he can kill penalties, so we get a player that can step in and help our group now. And with Noah we're getting a former first-round pick that's had some tough luck with injuries the last couple years. And he's from here and around here (Surrey, British Columbia), he's coming back home, he's excited to keep developing and we'll see where it ends up."
NHL.com independent correspondent Kevin Woodley contributed to this report
