A devastating drop in the stock of a struggling satellite company has put a spotlight on a pair of shareholders who partly escaped the carnage.

Intelsat, a Luxembourg-based satellite operator that provides TV and radio communications, has seen its shares plunge more than 85 percent as its plan to bag a windfall by selling its rights to valuable US airwaves has fizzled.

Last week, the Federal Communications Commission voted 3-2 to hold a public auction for the airwaves — scuttling Intelsat’s hopes for a more lucrative private sale — as the US looks to use the spectrum for an accelerated, nationwide rollout of high-speed 5G wireless networks.

“Shelling out billions for airwaves we already own is no way to handle taxpayer money,” US Sen. John Kennedy (R-La.) said after the FCC’s vote. “These foreign satellite firms want all four feet and their snout in the taxpayer trough.”

But two of Intelsat’s biggest investors, the buyout firms BC Partners and Silver Lake Partners, managed to sell a big chunk of Intelsat shares before the company’s hopes began to unravel last fall — and at least one other investor is weighing legal action over the situation, sources told The Post.

The saga kicked off in November, when Intelsat’s chief executive, Stephen Spengler, met with the FCC’s senior counsel, Nicholas Degani, to discuss Intelsat’s plan to sell spectrum in a deal that had been expected to result in a $7.4 billion payout to the company.

That meeting, which occurred on Nov. 5, was disclosed on the FCC’s website three days later.

On Nov. 6 — before notice of the meeting was posted — Bloomberg News reported that Morgan Stanley had sold a 10 million block of Intelsat’s shares for about $24.60 — a 6.6 percent discount to the previous closing price.

According to sources, the $246 million block was shopped after markets closed on Nov. 5. There was no advance warning that the sale was coming, and interested buyers were told they had an hour or so to decide, sources said.

Still, it seemed like a good deal at the time. Intelsat and other satellite companies were proposing to the FCC that they be compensated for easing off the airwaves, and Wall Street had been expressing confidence that the FCC would be amenable.

But after the Nov. 5 meeting, the tide turned against Intelsat. On Nov. 8, the company submitted a revised proposal offering to give up more spectrum in exchange for more money. The FCC rejected it 10 days later, on Nov. 18.

Instead, the FCC chose to pursue a public auction of its spectrum — a path advocated by Kennedy, who was against foreign satellite operators controlling the sale of government airwaves.

According to media reports, Kennedy said he spoke to President Donald Trump about the sale several days prior to the Nov. 5 FCC meeting. The president spoke to FCC Chairman Ajit Pai about Intelsat’s proposal on Oct. 30, an FCC official later told Reuters. The White House did not file a public description of the conversation because Trump did not express a view about how the spectrum should be sold, Reuters reported on Nov. 18.

A day after the FCC’s decision, on Nov. 19, Intelsat’s shares plummeted to $6.09, down 75 percent from the $24.60-a-share price that had been offered two weeks earlier. As of Wednesday, the stock was down 88 percent from that price, with the FCC last week approving a plan that could give Intelsat $4.87 billion in exchange for its licenses — a markdown of more than a third from what it had hoped to get.

“The balance sheets of private companies are not my concern,” Pai has said of the February plan to provide drastically reduced payments to satellite operators.

Two clobbered shareholders investigating the Nov. 5 block trade say Morgan Stanley at the time of the sale suggested to them the sellers were BC Partners and Silver Lake — Intelsat’s No. 1 and No. 2 shareholders at the time.

“Morgan Stanley more than intimated” it was BC and Silver Lake, one of the two stockholders told The Post.

BC Partners, known for its investments in PetSmart and public relations firm Teneo, is an Intelsat insider with a 34 percent stake and two seats on the board. On Feb. 12, its holding company Serafina reported selling close to 8.3 million Intelsat shares in the three months ending Dec. 31.

Silver Lake, which owns stakes in tech giants like Dell and Alibaba, as well as Madison Square Garden, reported selling 2.8 million of its 9.8 million shares in the fourth quarter, downgrading it to Intelsat’s fourth-biggest shareholder from the second biggest.

No specific dates were given for the respective sales by BC Partners and Silver Lake.

Intelsat declined to comment on the details of the FCC meeting or whether it discussed any of those details with its board, saying it does not reveal its private conservations with directors.

Morgan Stanley and Silver Lake declined to comment, while BC has denied any wrongdoing.

“The sales in question were executed based solely on available public information at the time and were executed in full compliance with all relevant market rules and regulations,” a BC Partners spokesman said.

A hedge fund investor who bought stock in the Nov. 5 block sale said he’s consulting with lawyers and reviewing his firm’s options for financial relief, including possible legal action.

“Our immediate reaction when the stock tanked was these f—ers knew something,” the hedgie said. “Even if BC only had knowledge of the FCC meeting, it was material.”

“We have called in a lawyer to examine this,” the angry hedgie said. “This does not seem kosher.”

A second Intelsat investor said he, too, is angry and wants answers. He said he passed on the Nov. 5 block sale, but attributed that to dumb luck as he was crushed on the stock with everyone else a few weeks later.

“I think they must have known something was going on,” he said of the Nov. 5 sales. “It should be looked into. They were in a position to have much more information than me,” he said of BC Partners.

Securities lawyer Jordan Thomas of Labaton Sucharow says the timing is sure to pique regulators’ interest.

“The timing, size, and other circumstances surrounding this transaction raise red flags,” said Thomas, a former Securities and Exchange Commission enforcement lawyer. “Time will tell whether insider trading occurred, but there’s no doubt in my mind that the SEC will open an inquiry.”