The takeover of former bank holding company Washington Mutual by financial service provider JPMorgan Chase is set to cause a stir on the signature-based debit card market and raise the stakes of the competition between the largest two card issuers on the US market – Visa and MasterCard, reports a recent study.

JP Morgan Chase’s acquisition of Washington Mutual comprises all the company’s assets, including WaMu’s former branch network, all of its deposit liabilities as well as its debit portfolio. Three years ago, Washington Mutual chose to convert its 10 million debit card portfolio from Visa to MasterCard, however in light of the recent takeover, analysts say a lot hangs on JP Morgan Chase’s decision regarding the branding of Washington Mutual’s portfolio.

If Chase officials decide to prolong their issuing agreement with MasterCard, researchers see this as a possible indicator of MasterCard’s ability to effectively tackle rival company Visa and increase its market share. However, JPMorgan Chase is known as a Visa-oriented debit card issuer, as the majority of its over 12 million signature debit cards currently outstanding are Visa-branded. MasterCard however announced it is determined to continue its market share expansion as well as its strategy to provide incentives to issuers and merchants to issue cards under its brand. The study was carried out by financial research provider Aite Group.