The Credit Suisse surveillance scandal was long in the making: top banker Iqbal Khan reportedly wanted to lodge a criminal complaint against CEO Tidjane Thiam, but didn't for professional reasons.

The September run-in between star banker Iqbal Khan and a private detective working for Credit Suisse, where he was still under contract, was even longer in the making than originally reported: Khan and his boss, CEO Tijdane Thiam, had words at drinks for neighbors in the CEO's home to mark the new year last January (it isn't clear over what).

The spat between the two Credit Suisse bankers, also neighbors in a cushy lakeside suburb of Zurich, now appears to involve more than several arborvitae shrubs on their shared property line, according to Swiss weekly «SonntagsZeitung» (behind paywall, in German). The Swiss outlet reported that private banker Khan felt the CEO's behavior towards him warranted police notification

Weighing Police Report

The outlet didn't specify the nature of CEO Thiam's behavior towards his subordinate. Several people familiar with the relationship dynamic between the two men describe Khan as being intimidated by Thiam's behavior.

After the January confrontation, Khan considered a criminal complaint against Thiam, but stopped short of doing – though he did discuss the incident with Credit Suisse Chairman Urs Rohner. The chairman mediated a peace treaty between the two bankers – which led Khan to drop any plan of involving police, according to «Sonntagszeitung».

Top Executive Sacked

The minutae leading up to the shocking September scuffle is indicative of the high stakes – and heightened tensions. Khan was long considered the key internal successor to Thiam, but defected to UBS in August. «Sonntagszeitung» reported that Credit Suisse also shadowed Khan's wife, and that his two school-age children also warrant mention in surveillance reports.

It has since emerged that Credit Suisse had at least one other of its top executives – Peter Goerke – also tailed. The Swiss bank found its former operating chief Pierre-Olivier Bouée, singlehandedly coordinated the surveillance, for which it sacked him retroactively.