The trade gives the Sharks depth up front that they were seeking and gives the Penguins a needed high pick after trading their first and second-rounders before the deadline for forward Jarome Iginla and defenceman Douglas Murray.
General manager Doug Wilson said he had been targeting Kennedy for about a year and said he will be an important piece in the present and future for the team.
"He's a guy that for us fits perfectly with how we want to play and the type of ingredients that he brings filling out our top nine," Wilson said. "He can go up and down, he plays with an edge, he can score some goals. That's the type of player we've been looking for. Not only additional scoring but maintain the identity that we tried to build with our team the last year in particular."
Pittsburgh acquired San Jose's pick, 50th overall, in the second round. The Penguins had been slated to make their first pick at No. 77.
The Sharks later traded up two spots in the first round with Detroit to select Swiss defenceman Mirco Mueller 18th overall. San Jose gave up the 20th pick and Pittsburgh's second-rounder, 58th overall, to get Mueller, who played last season for Everett of the Western Hockey League.
"He can play all over the rink," Sharks scouting director Tim Burke said. "He gets the play started and he kills a lot of plays. We got a lot of good reports on him."
The Sharks acquired the pick from the Penguins from an in-season deal that sent defenceman Douglas Murray to Pittsburgh. San Jose also will get a 2014 second-rounder from Pittsburgh in the Murray deal.
The Sharks still had one second-round pick from the deal that sent Ryane Clowe to the New York Rangers and took forward Gabryel Boudreau 49th overall. Boudreau had 22 goals and 41 assists in 67 games with Baie-Comeau in the Quebec Major Junior Hockey League.
Mueller had six goals and 25 assists in 63 games this season. The 6-foot-3, 176-pound Mueller is considered a mobile defenceman with the ability to create offence. He was ranked as the ninth best North American skater and third best defenceman heading into the draft by NHL Central Scouting.
"It's a great day for me," Mueller said. "I play a simple game, a puck-moving defenceman. I try to make plays from my own end and try to get it forward."
Kennedy had six goals and five assists in 46 games last season and adds needed depth to the Sharks' forward contingent. He also had two goals and three assists in nine playoff games.
But Kennedy was often a healthy scratch as the Penguins made it to the Eastern Conference final before being swept by Boston and got the sense from general manager Ray Shero after the season that he wasn't in Pittsburgh's plans.
"I thought I had a great playoff," Kennedy said. "I'm kind of stumped. I'm really kind of lost why they didn't want me more. I think I'm a great player."
Kennedy has 76 goals and 92 assists in 372 career games with Pittsburgh. He also has 12 goals and 15 assists in 76 career playoff games, helping the Penguins win the Stanley Cup in 2009.
"I think I'm an energy guy," Kennedy said. "I think I bring a lot of energy to the ice and I think I have a good skill set. I try to finish my checks when I can."
Kennedy is one of two pending restricted free agent forwards on the Sharks, joining TJ Galiardi. San Jose has to decide whether to tender qualifying offers to both players by Tuesday.
The free agency period starts Friday and the Sharks have about $3.6 million of salary cap space with 19 players under contract, according to CapGeek.com. But forward Marty Havlat could provide cap relief if he begins the season on long-term injured reserve following off-season surgery.
Kennedy said he would like to sign with San Jose.
The Sharks have been busy already this off-season, signing potential unrestricted free agent Raffi Torres to a $6 million, three-year deal, and agreeing to a five-year extension with star centre Logan Couture that keeps him off the free agent market next summer.
San Jose has also signed potential restricted free agent forwards Andrew Desjardins and James Sheppard and defenceman Jason Demers to contracts.
San Jose also made a trade with Chicago to move down six spots in the fourth round and selected Swedish goalie Fredrik Bergvik.
San Jose got a fifth-rounder in the deal and sent the Blackhawks a 2015 fifth-round pick. That gave the Sharks two fifth-round picks this year and they took defenceman Michael Brodzinski from Muskegon of the USHL with their own pick and defenceman Gage Ausmus, who is planning to play at the University of Denver, with Chicago's.
San Jose finished the draft by taking Minnesota centre Jacob Jackson of Tartan High School in Oakdale, Minn., and Russian left wing Emil Galimov in the seventh round.