A recent court ruling could make the commonwealth liable for more than 100-million-dollars in tax refunds to businesses. The ruling came in a case that arose over provisions outlining how companies can use past losses to lower their tax bills. Some corporate taxpayers have claimed successfully that provisions, that have since been dropped, violated the state constitution. Now, state courts are dealing with how to handle tax payments that were made when those unconstitutional provisions were in effect. Two pending cases involve telecom companies Alcatel-Lucent and Nextel.