1 Introduction  
2 Known Characterizations of GIG Laws  
2.1 A Characterization by Continued Fractions  
2.2 The Matsumoto-Yor Property  
2.3 Characterizations by Constant Regression  
2.4 Entropy Characterization  
2.5 Some Characterizations of the IG Distribution  
3 New Characterizations of GIG Laws  
3.1 An MLE Characterization  
3.2 A Stein Characterization