The country’s largest e-cigarette maker Juul Labs continued its astronomical rise from startup to vaping behemoth by finalizing the terms of its latest deal with Big Tobacco firm Altria Group (MO).

The $12.8 billion deal, which Altria announced Thursday morning, is slated to give the maker of Marlboro a 35% stake in Juul, valuing the less than two-year-old vaping company at $38 billion.

The new valuation is more than double the $16 billion valuation Juul last earned when it raised $650 million from investment fund Tiger Global just five months ago this summer. At that point, Juul became the fastest startup ever to reach a valuation of more than $10 billion dollars — beating the pace set by tech giants Facebook and Snap by four times.

“This is a unique and compelling opportunity to invest in an extraordinary company, the fastest growing in the U.S. e-vapor category,” Altria CEO Howard Willard said in a statement announcing the deal.

But while that growth is attractive for a tobacco company that has seen sales of its Marlboro cigarettes drop more than 3% in the most recent 52-week period compared to Juul’s 941% explosion in the same timeframe, the question inevitably on investors’ lips will become “Did Altria overpay?”

By voting to invest in Juul at a valuation of $38 billion, Altria’s board made the calculation that Juul is worth twice as much as Lyft, or about $8 billion more than Airbnb and Elon Musk’s SpaceX. At $38 billion, Juul even surpasses the size of some well-known publicly traded companies like Target (TGT) and Ford (F). Not bad for a company that was spun off from parent company Pax Labs less than two years ago.

Altria funded the deal to acquire its minority stake in Juul with a $14.6 billion one-year term loan through JPMorgan Chase, a decision that will carry its interest costs into 2019 and beyond. Addressing that concern with investors on a call Thursday, Willard said the company would mostly offset those expenses with cost savings of around $600 million in 2019.

“We remain committed to maintaining our investment grade credit rating,” he said.

Of course, Juul’s rise to prominence has also come shrouded in controversy as the startup has increasingly faced scrutiny from the U.S. Food and Drug Administration for playing a role in what the agency labels as a teen vaping “epidemic.” Studies from the Centers for Disease Control and other medical professionals have pointed to a near doubling in the percentage of high schoolers who vape in just the past year. Anti-tobacco advocates argue that underage teens purchasing Juul’s products have played a non-trivial role in the e-cigarette maker seeing it’s sales skyrocket to nearly $2 billion a year.