From 2004 to 2009, P worked at Citicorp's (D) call center. As a condition of employment, he signed a standard contract to arbitrate his disputes with the company. The agreement covered individual claims but not class actions. In January 2012, P filed a class action against the company. He claimed that the company did not pay its employees for time spent logging into and out of their computers at the beginning and end of each workday. Because the arbitration agreement with P did not reach class claims, the company did not seek arbitration. P applied to work once more at D's call center. D agreed to rehire him. By this time, D's standard arbitration contract now covered class claims as well as individual ones. P signed the new contract, and in January 2013 he began work in the call center. P did not consult with his lawyers before signing the new contract. The lawyers directly representing D in this case, an outside law firm, did not know that P had applied to work at the call center. They found out sought to compel P to arbitrate the class action, which by then had begun discovery. The court concluded that the new arbitration agreement did not cover lawsuits commenced before the agreement was signed. D appealed.