A federal judge in New York has issued a restraining order temporarily blocking Aegean Marine Petroleum Network’s $367m purchase of HEC Europe from the bunkering giant’s founder and former largest shareholder.

In a sharply worded rebuke of the proposed deal, US District Judge Loretta Preska said that the transaction with oil tycoon and shipowner Dimitris Melissanidis is not fair because there was no attempt to seek a shareholder vote and was timed before the company’s annual meeting.

As TradeWinds reported at the weekend, three rebel shareholders lodged a federal lawsuit against bunkering giant Aegean Marine and its board members, arguing that the embattled effort to buy ship waste disposal firm HEC from Melissanidis should not go through. Melissanidis owns HEC Europe and is a former major shareholder at Aegean.

The Tyler Baron-led plaintiffs, whose RBM Holdings owns 4.5% of New York-listed Aegean’s shares, make up part of the 12.8% stake held by activist Aegean shareholders who have sought to nominate a new board and then to resist the HEC deal.

In a ruling obtained by Trade­Winds, Preska sided with the plaintiffs, arguing that it is in the public interest to ensure that shareholders’ vote is sacrosanct. And she said the pricing of the transaction could inflict irreparable harm on shareholders.

She also noted that the board is repurchasing Melissanidis’ shares at $4.45 apiece within 18 months of buying all of his shares at $8.91.

“Here, the timing of the transaction is highly suspect,” she said. “After receiving notice of the plaintiff, that is, the committee’s decision to nominate a competing slate of directors, the board scheduled the acquisition to close before the annual meeting,” she wrote.

Aegean could not be immediately reached for comment on the ruling.

But the company’s lawyers told a US federal court in New York this week that a temporary restraining order sought by Tyler Baron-led RBM Holdings failed to meet legal muster and threatened a deal that is vital to the future of the marine fuel supplier and tanker owner.

“The transaction confers substantial benefits on Aegean, and it is critical for the success of Aegean that the transaction close — and on time — before the transaction is subject to termination at will [by HEC],” said Aegean’s lawyers, led by Arthur Aufses of Kramer Levin Naftalis & Frankel.

They added: “A small minority — holding 4.5% of Aegean’s stock — should not be permitted to inflict hardship on the company and the holders of the vast majority of its shares.”

The deal would give Melissanidis 33% of Aegean Marine after the issuance of new shares. Combined with the shares of its largest shareholder — shipowner and former chairman Peter Georgiopoulos — “Melissanidis-aligned” insiders would be able to block changes to the board of directors, the lawsuit alleged.

A source close to Georgiopoulos says the veteran shipowner “is not aligned with Melissandis nor has he been”.