Also, in order to ensure proper market formation, two limits are applied in terms of issues and issuers, calculated in nominal values. On the one hand, the ECB won’t buy more than 25% of each issue. The 25% issue share limit is applied in order to avoid a blocking minority in the event of a debt restructuring involving collective action clauses (CACs).
Liquidity in some markets could dry up causing spreads to widen further as investors would try to reduce their exposures. And  2  BIS Review 120/2006  currencies in the region could come under pressure to weaken as investors would try to exit certain markets.