A power struggle atop Credit Suisse is likely to end in favor of embattled CEO Tidjane Thiam – who enjoys the support of the wealth manager's weightiest shareholder. The investor is asking for another major change instead.

It has become a reliable pattern: when things get precarious for Tidjane Thiam, the Credit Suisse CEO's biggest backer is never far. David Herro, who oversees international stocks at U.S.-based fund manager Harris Associates, is the Swiss bank's biggest shareholder with roughly 9 percent.

The Chicago-based veteran investor is upping his rhetoric – and also subtly tipping the balance in favor of Thiam, and against long-standing Chairman Urs Rohner, in an interview with «Bloomberg». Herro, who frequently telegraphs via the press, makes it unmistakenly clear that he wants the CEO to stay despite a tawdry spy scandal in the C-suite.

Spying is «Little Issue»

Herro told the outlet that Harris and other, undisclosed big shareholders back Thiam «100 percent». «People don’t want to see the board or anyone tinkering with management,» he said. Other major shareholders include Norwegian sovereign wealth fund Norges, U.S. giant Blackrock, and Saudi Arabia's Olayan family.

The straight-talking fund manager didn't provide any evidence for the broad, bold claim that he speaks for more shares than Harris itself owns; Norges declines to comment while the other two shareholders didn't respond to a request for comment.

Herro argued that Thiam had done excellent work turning around Credit Suisse, and termed a surveillance scandal in the C-suite as a «little issue» with scant relevance outside of Paradeplatz, the symbolic home of Swiss banking.

Competitive Spite?

Repeated attacks on Thiam appear driven by competitors out of envy or racism, Herro said, «given that Mr. Thiam looks a little bit different than the typical Swiss banker.» His timing is impeccable: Credit Suisse's board is convening for a previously scheduled meeting on Tuesday. Given the shelling the bank is under, directors are expected to focus on the surveillance scandal.

Instead of Thiam leaving as a result of the scandal, Herro argued that his boss, Chairman Rohner, should exit swiftly. He said Credit Suisse's board should focus instead on replacing Rohner next spring when term limits kick in. This contravenes a previous report that Rohner's intention is to argue forEric Varvel, a Credit Suisse stalwart who currently oversees its U.S. arm, and Thomas Gottstein, its Swiss boss, to jointly take over from Thiam (Rohner denied the report).

Protecting Investment

Herro's remarks represent a tactical defense measure in favor of Thiam, who has spent the last three to four years turning Credit Suisse into a more focused wealth manager and replenishing its capital. Harris Associates has no interest in ructions to Credit Suisse's share price that a management change would likely induce.

Harris and other big shareholders ensured Credit Suisse was flush through two cash calls since 2015 – and wants to protect its investment. In the last 12 months, Credit Suisse's stock outperformed the wider European banking sector.