Almost immediately after the Pennsylvania Supreme Court issued its game-changing workers’ compensation ruling in Protz v. Workers’ Compensation Appeal Board (Derry Area School District) last year, attorneys began gearing up to litigate the natural follow-up question: Should the decision be applied retroactively?

A much buzzed-about June 6 ruling by the Commonwealth Court en banc may have finally answered that question. “May have” is the operative phrase, however, because not everyone agrees on the potential significance of the decision. The confusion appears to boil down to competing definitions—or, perhaps more accurately, expectations—of “retroactive application.”