From the beginning, the Eurosystem's collateral framework granted eligibility status to marketable securities traded on either regulated or non-regulated markets (ECB 2000/7). Regulated markets include exchanges such as the “Frankfurter Wertpapierbörse (Regulierter Markt)” operated by Deutsche Börse AG and “Eurex Deutschland” operated by Eurex Frankfurt AG in Germany as well as “Euronext Paris” and “MATIF” operated by Euronext Paris in France, or the “Wholesale Italian and Foreign Government Bond Markets (MTS)” operated by Società per il Mercato dei Titoli di Stato – MTS S.p.A. in Italy. On October 4, 2014, for example, the list included eighty-eight regulated markets.

Examples of non-regulated markets that are currently accepted by the ECB include the “STEP market” in the EU, the “French Medium-Term Notes (BMTN) market,” and “the unofficial market (Freiverkehr) of a German exchange.” On October 4, 2014, the list included twenty accepted non-regulated markets.

While securities could potentially trade on different types of markets, the initial collateral framework described in ECB (2000/7) specifies that collateral issued by credit institutions is only eligible if it trades on a regulated market, except in the case of covered bonds.

Thus, unsecured debt issued by credit institutions, or banks for short, trading on non-regulated markets was not eligible collateral, except in exceptional circumstances at the discretion of the Eurosystem.

This changed after the Lehman bankruptcy in the fall of 2008. In particular, as of October 25, 2008 (ECB 2008/11, Article 4):

Hence unsecured bank bonds trading on non-regulated markets are subject to eligibility from October 25, 2008. As shown in Table 5.2, bank debt trading on non-regulated markets was initially subject to an additional haircut of 5 percent as compared with corresponding instruments trading on regulated markets. This reflects the increased risk and illiquidity of such collateral. Nevertheless, this extra haircut was later dropped (see Tables 5.3 and 5.4). I will refer to the inclusion of unsecured bank debt trading on non-regulated markets into the public list of eligible collateral as the “non-regulated markets inclusion clause.”