Rocket Lab Corp. (NASDAQ:RKLB) had not seen its stock downgraded in more than 18 months—but the streak came to an end when KeyBanc Capital Markets downgraded RKLB from Overweight to Sector Weight on Thursday. 

While the firm still considers Rocket Lab a high-quality leader in the space sector, the stock's recent surge has fully priced in several major growth catalysts. 

RKLB stock is sinking. See the chart and price action here. 

It's Already Priced-In

The downgrade is primarily driven by the belief that the company's recent successes are well-known and reflected in its current valuation. The milestones include:

Major Contract Awards: In December, Rocket Lab secured an $816 million contract from the Space Development Agency for Tranche 3, nearly doubling its backlog.

Infrastructure & Technology: The ...