However, the Welsh region have confirmed they are in talks with fly-half Rhys Patchell over a potential move from Cardiff Blues.
New Zealander Pivac dismissed stories linking North with a return to the team he left in 2013 as speculation.
"George North is media only, so don't ask that question every week because we're not chasing him," he said.
"Rhys Patchell, he's one that we are talking to, he's certainly one who is of interest to us."
North has played 55 times for Wales and made three appearances in Tests for the British and Irish Lions during the 2013 tour of Australia, scoring two tries.
His contract with Saints ends in the summer of 2016, and had been strongly linked with a return to west Wales.
Patchell, who has played twice for Wales, is reported as having told the Blues he wants to leave when his contract expires at the end of this season.
A fly-half by preference, Patchell has played a lot of his rugby at centre and full-back since the arrival of Gareth Anscombe from New Zealand in November 2014.
Blues head coach Danny Wilson believes Patchell needs to do what he considers the right thing for his career.
"It definitely won't be about money it will be a rugby decision and a decision that Rhys believes is best for him," said Wilson.
"I think this has been going on a lot longer than this season if I'm brutally honest.
"Rhys will make the relevant decision when necessary, but we want Cardiff Blues to be full of players that want to play, want to compete for Cardiff Blues and if anybody doesn't want to then they plain and simply shouldn't be here."
Scarlets are "not chasing" Northampton and Wales wing George North, according to head coach Wayne Pivac.