If Anglo Irish Bank's liquidators opt not to appeal against a legal ruling that found "burning" subordinated bondholders with steep losses was wrong, then other banks can expect to be hit with their own claims.
Bank of Ireland and AIB in particular are vulnerable to legal challenges from disgruntled bondholders.
That's because techniques similar to those employed by Anglo were used to inflict losses on some lenders to those banks, too.
Up to now, bondholders have been holding back, waiting for the outcome of the planned appeal in London before spending cash on any uncertain legal challenges of their own. The numbers involved are big.
Bank of Ireland and AIB each saved about €2bn by forcing losses on their junior bondholders. Irish Life & Permanent and EBS Building Society also saved smaller but considerable amounts with similar actions.
In most cases, bondholders voted to accept a payout rather than wait for the cosh to fall, and they may struggle to resurrect their original claims. A minority of investors, however, are in a similar legal position to Asseganon, which last year won a legal victory against the coercive actions of Anglo.
Investors who did take the biggest hit are armed with a legal precedent that effectively says it should not have happened; we can expect to hear from them very quickly.
Interestingly, a technique similar to that employed by Anglo was used to force losses on lenders to the Greek government last year. It is potentially open to challenge, too.
Spain, on the other hand, held back from using the Irish model to share the losses at its banks with subordinated bondholders, in large measure because of the Asseganon ruling.