iPhone unlocked?

Easiest way to find out is to try a sim card from a different carrier in it.

If it works, its unlocked, if it doesn't, then you know its locked.

However, since it was sold by Verizon, unless it was explicitly sold as unlocked, its very likely locked to them, specially if bought under contract with Verizon.

If you purchased it as Verizon, then it is locked to Verizon. The only place to purchase an unlocked phone is the Apple Store. If you want to have it unlocked, you need to ask Verizon to unlock it.

You're welcome.