Serve as a primary point of contact for internal and external billing inquiries, responding to requests for payment history, cost details, and other financial information; investigate and resolve billing discrepancies and client requests for cost back-up documentation; input and maintain accurate client and matter data, including rates, fee arrangements, and billing guidelines, within the firms financial system; audit time and expense narratives for compliance with client rules before bill generation. Responsibilities: Review, interpret, input, track, and manage Outside Counsel Guidelines (OCGs) and complex client billing rules, ensuring all invoices and time entries strictly adhere to client specifications; act as the firms subject matter expert on client-specific billing requirements, proactively communicating updates, restrictions, and best practices to attorneys and support staff to minimize reductions and rejections.