Why Did Firefly Stock Jump?
For questions about this article or underlying research, email help@trefis.com.
Firefly Aerospace (FLY) stock climbed 36.8% on Friday, November 6, 2026, while the S&P 500 gained 0.3%. That day, the company signed a rocket engine deal with AST SpaceMobile valued at more than $1.3 billion, and shares of Rocket Lab and Intuitive Machines also rose sharply. How big is that deal for a company of Firefly’s size?
How Big Is Firefly’s Engine Deal With AST SpaceMobile?
The agreement alone is worth nearly as much as Firefly’s entire backlog, representing the work customers had already contracted the company to deliver. On its August 11 call, management placed that backlog at about $1.5 billion as of the end of June 2026. For scale, Firefly generated $287 million in sales over the twelve months to June 2026 and held a stock market value of about $3.4 billion at Friday’s close. The three-year agreement covers engine deliveries, licensed IP, and engineering support.
AST SpaceMobile will purchase 36 rocket engines from Firefly before licensing the right to manufacture more. The buyer will use these Miranda and Vira engines to power Blacklift, a 20-ton rocket it is building to deploy BlueBird satellites in low Earth orbit. Management said on its August 11 call that Firefly was still qualifying Miranda for its own Eclipse rocket, which it is developing with Northrop Grumman. The company said the deal brings in additional funds to speed up production of its own launch vehicles.
Did Firefly Rise With Other Space Stocks?
Partly, but Firefly rose far more. Rocket Lab advanced 15.4% during the same session, while Intuitive Machines climbed 22%. The other names on Firefly’s peer list, Lockheed Martin, Northrop Grumman, and Boeing, each moved less than 2%, and the industrials sector fund, XLI, rose 0.1%.
Space and defense stocks had retreated on Thursday, November 5, when concerns about military spending after Democrats’ midterm gains weighed on the sector. Firefly itself fell 11.6% that day. Its Friday rise was more than twice Rocket Lab’s.
Firefly Stock Still Sits Far Below Its May High
Firefly stock has not recorded a rise like this in at least a year, with no single session in the prior 365 days bringing a gain this large. Even so, the stock is down 7.7% over the past twelve months, trailing a 9.8% gain for the S&P 500. Shares closed at $20.76, remaining far below their highest close of the past year, $58.81 on May 26, 2026. The stock lost 47.7% over the six months to November 6, and its $15.18 close the day before the jump marked its lowest in a year.
A one-year low, then a 36.8% jump the next day. Build a portfolio that can take both.
Because Firefly lost money over the past twelve months, sales offer a clearer yardstick for the price investors pay. The stock trades at 11.7 times its trailing twelve-month sales, against 3.1 for the S&P 500. Firefly is expected to report its third-quarter results later in November 2026, its first report since the AST SpaceMobile deal, and its backlog is the figure to watch.
Sitting On A Big Gain In Firefly Aerospace?
Hold, trim or sell: the tax bill can decide more than the stock does. A free 30-minute strategy review with our partner advisory firm covers ways to protect the gain and unwind it with less tax.
Spot an error or want more like this? Tell us in 10 seconds.