The manager of the top-performing small-cap fund this year outlined his 4 criteria for finding strong investments — and revealed his 3 favorite hidden gem stock picks right now

The manager of the top-performing small-cap fund this year outlined his 4 criteria for finding strong investments — and revealed his 3 favorite hidden gem stock picks right now

With a name like the Needham Aggressive Growth Fund, you’d be forgiven for thinking that portfolio manager John Barr…