As 2018 winds down, George Economou's already huge stake in Dryships has only gotten larger.

According to Securities and Exchange Commission filings, the Greek tycoon owns 82.5% — or 72.4 million — of the New York-traded outfits' outstanding shares through SPII Holdings, an increase of nearly 12% since the year started.

Economou has bought no new shares. The increase comes thanks to two, back-to-back $50m buyback programs, the first announced in February and the second in October.

Most recently, a buyback on 27 November bumped his stake over the 80% mark, while two more on 7 and 17 December bringing him to his current mark.

The moves come during a year in which Dryships has dealt with both good news and bad news.

The company was the top performing US-listed shipping company in the first half of 2018, according to Stifel.

But it also faces a legal battle with shareholders — and an investigation by the SEC — after allegedly destroying nearly all shareholder value by issuing new shares through a British Virgin Islands underwriter and keeping the price up through a series of reverse splits.

The shareholders allege Economou owned less than 1% of the company at one point to protect himself from the scheme and his ownership has only grown since then.

Dryships and Economou have denied any wrongdoing.

In March, filings show Economou owned 70.6% of Dryship's 102.5 million shares, split between SPII, Sierra Investments and Mountain Investments.

In June, Sierra and Mountain no longer owned any shares, with SPII picking up their stakes. The two have not been involved in the company since.

Meanwhile, Dryships stock hit a 2018 low of $2.81 in early February, just before the buyback was announced. In midday trading Friday, Dryships was trading around $5.47. The 52-week high is $6.53, posted in late June.