As arbitration becomes an increasingly popular mode of resolving disputes, neighboring industries begin to take notice. This interest is reflected in the increasing utilization of third party funding in international arbitration claims. In this regard, the third party funding industry appears particularly interested in investor-state arbitration claims because they typically involve considerable claim amounts and substantial legal fees. To examine this trend more closely, this paper, firstly, examines the investor-state arbitration more precisely in Chapter II. In Chapter III, this study continues to examine some legal issues which can arise as a result of a conflict of interest between the parties to the funding agreement including, inter alia, 1) a dispute in which the funder terminates the agreement during the arbitration proceedings, 2) a dispute in relation to a funder's intervention in arbitration proceedings, and 3) a dispute on the responsibility for adverse costs orders, if any. This paper further identifies major legal issues which can arise in relation to 1) disclosure of existence of the funding agreement, 2) attorney-client privilege. Lastly, in Chapter IV, this paper provides some lessons from an in-depth case study on third party funding agreements and solutions to avoid and to solve prospective disputes in the future.