Most any folding knife, whether it's a multi-blade pocketknife or a single-blade folder, will benefit from a bit of oil on the pivots from time to time.
Over the years we've used light machine oil, gun oil and various household oils, but the best product we've found for maintaining our folding knives' pivots is Benchmade BlueLube.
Whatever you decide to use, don't over-lubricate -- a drop or two is all you need. Anything more will only attract dirt and gritty particles that'll eventually cause wear.
Here's another tip: During your new knife's break-in period, don't lubricate it.
The pivots of folding knives are lubricated when they're assembled -- with oil, light grease or graphite powder -- and the maker applies only a small amount of lubricant, to avoid interfering with normal break-in.
We know it can be tempting, with a new knife that's stiff or sticky, to apply oil to the pivot immediately. That may soften the action, but it'll also postpone (or prevent) the break-in process.
Be patient. Let the surfaces "mate" naturally. When you notice your knife begin to become smoother, then you can add a drop or two of light oil.