According to Rob Rossi of The Athlectic, while the Penguins are interested in Tatar, they will likely only offer him a professional tryout if he doesn't sign a guaranteed contract before camp begins.
Tatar, 32, spent last season with the New Jersey Devils where he appeared in all 82 games recording 20 goals and adding 28 assists for a total of 48 points.
While PTO's are more common in recent years due to cap constraints, a player like Tatar, especially coming off a season like he had last year should not bd a player that has to sign a PTO to keep his career alive, alas, it might turn out that way if another team doesn't come along and sign Tatar to a guaranteed contract.