PITTSBURGH -- Letters are being sent out to convince local health care workers to be part of a class action lawsuit against three local health systems.

On Thursday a New York-based law firm announced 100,000 employees of area hospitals will get letters inviting them to join a class action lawsuit to recover wages for missed lunches.

The hospitals are UPMC, the former Mercy hospital, and West Penn Allegheny Health System.

The lawsuit claims hourly employees who worked during a lunch break or were interrupted during lunch for work are owed back wages. Now they want to notify all employees of their rights to join the lawsuit.

"Its important to note in these cases participation is not automatic. An employee actually has to physically return the form if they want to ask for back wages in these cases. If they do not return in 60 days, they risk not being able to recover in these lawsuits," said Attorney Nelson Thomas.

UPMC responded , saying they will vigorously defend themselves against a lawsuit.