The agreement also included a clause that neither would make "any disparaging comment" about the other to anyone else.
Lewis claimed JPMorgan Chase breached that agreement but in October 2012 the ERA rejected a complaint he made to it.
The following month Lewis - whose LinkedIn profile says he now works at Bank of New Zealand - filed a claim against JPMorgan Chase in the Employment Court. In this action, Lewis wants $170,000 in damages and a declaration his employment contract was breached, says Chief Judge Colgan's decision.
Lewis, according to that judgment, claims that when he applied for a position with Westpac in 2010 he said he was JPMorgan Chase's local chief executive, but when Westpac checked this his former employer allegedly denied it.
Lewis claims that despite a subsequent attempt to have JPMorgan Chase correct its records "he both lost the opportunity for employment and suffered distress" during the next six months before he found work. He is seeking $50,000 in damages for this alleged "distress" as well as $120,000 for lost income.
In July last year, JPMorgan Chase applied to have Lewis' claim against it struck out. Chief Judge Colgan declined to do so. In his judgment, Colgan said a "relatively simple case" in the ERA "has blossomed into full-blown adversarial litigation".
JPMorgan Chase are fighting the decision on the strike out and yesterday applied for leave to challenge it at the Court of Appeal.
Lewis' lawyers opposed this bid and Justices Lynton Stevens, Douglas White and Christine French reserved their decision on the application.