The US Marine Corps' F-35B short take-off vertical landing variant of the "Lightning II" has completed its first set of engine air start tests. That means that the F-35B will be able start high alpha testing next year--the US Air Force's F-35A model will be starting that work later this month.
Both versions of the jet will have an angle-of-attack limit of 50 degrees, which is comparable to the Boeing F/A-18. But while the F/A-18s top out at about 50 degrees AOA--though with some effort one can momentarily exceed that--the Hornet/Super Hornet doesn't have an alpha limiter. Neither does Lockheed Martin's other 5th generation fighter, the F-22 Raptor.
At the Farnborough air show in July, Lockheed F-35 test pilot Al Norman told me it was a safety feature... But it's still kinda curious as to why the company and F-35 Joint Program Office chose to have a hard 50 degree limit.