A key shareholder in Golar LNG is selling just as another key investor bumps up its position in the troubled gas carrier owner.

Cobas Asset Management — the Tor Olav Troim-backed company's second-largest shareholder — has sold more than 522,000 shares, according to regulatory filings.

The Spanish investment firm now owns 9.65m shares, down from 10.2m, giving it a 9.9% stake in the company.

The sale comes amid a bribery investigation in Brazil implicating Hygo Energy Transition's chief executive Eduardo Antonello in paying off Petrobras officials when working for Seadrill in 2011.

Hygo was expected to begin trading on New York's Nasdaq late last week, but news of the investigation postponed the company's debut.

Golar LNG said it was launching an investigation into Antonello's conduct during his tenure with the company, but stressed the allegations stemmed from his time with a non-Golar LNG outfit.

Hygo, formerly named Golar Power — a joint venture between Golar LNG and Stonepeak Infrastructure Partners, will run Golar LNG's former downstream gas assets.

Antonello, who has denied the allegations through his attorney, has taken a leave of absence from the company to deal with the investigation.

It is unclear when Hygo trading will begin, but the spin-off was expected to add significant value to Golar LNG shares and the uncertainty has caused investors to flee the company.

On Thursday, Golar LNG shares gained nearly $0.90, closing at $6.94, but lost nearly half its gains in after hours trading.

Ahead of the opening bell on Friday, shares were trading at $6.54.

Golar LNG was trading as high as $11.08 before news of the Antonello investigation began.

The fall in share prices saw Andreas Sohmen-Pao's BW Group snap up nearly 440,000 shares midweek when shares dipped below $6.

BW is the company's fourth-largest shareholder, with 5.64m shares.

Both BW and Cobas trail Orbis Investment Management, which owns 11.1m shares or 11.3% of the company.

Orbis has not yet bought or sold any Golar LNG shares.

Last week, Stifel analyst Ben Nolan said the investigation had injected additional risk into the stock, but the depressed price could be an "absolute gift" to investors if they were willing to take the chance.