Correct!

In New York, what usually decides coverage for an employee hurt while joining in horseplay is whether that kind of play had become an accepted, ongoing part of the workplace.

New York’s highest court drew this line in Ognibene v. Rochester Manufacturing Co. (1948): an isolated prank generally falls outside the employment, while a practice the workplace has come to accept becomes part of it. That is why consistent enforcement matters more than a handbook rule alone. Bystanders hurt by horseplay they did not take part in are generally covered.

Learn more here: The Horseplay Rule Demystified