My understanding of the classification is as follows:
1st Generation: These are researchers who began researching the assassination right at the beginning or very close to it. This would include David Lifton, Harold Weissberg, Robert Groden, Mark Lane, Jim Marrs.
2nd Generation: These are researchers that arrived on the scene after the new wave of publicity that surrounded the JFK assassination with the new 1978 HSCA investigation. This would include the likes of Vince Palamara.
3rd Generation: These are researchers that arrived on the scene after the new wave of publicity that surrounded the JFK assassination with the release of the 1991 JFK movie and subsequent release of new files via the ARRB. This would include people like David Mantik and Jim DiEugenio (though maybe DiEugenio is 2nd generation i'm not sure).
Is this a correct interpretation of the classification of 1st, 2nd, 3rd generation JFK researchers?
Has the 4th generation started yet?
1st generation should include Sylvia Meagher, Vince Salandria.
Definitely worth reading.
Salandria died just recently; there's a thread on him.