Those aren't authentic IMO. Here are some authentic examples to get you more familiar with her signature.
Complete Authentic Signature: (RARE)
Authentic Full Rush Signature Personalized: (RARE)
Authentic Full Rush Signature: (RARE)
Authentic Complete Signature + Personalization and Rushed IP signature:
Her new Current Authentic Full Signature: (Has a bar under it and loopier L)
Super rushed authentic signature:
Neat Rushed Signature:

Those aren't authentic IMO. Here are some authentic examples to get you more familiar with her signature.
Complete Authentic Signature: (RARE)
[img]http://sarahsautographsite.webs.com/photos/Actresses/jennifer.jpg[/img]
Authentic Full Rush Signature Personalized: (RARE)
[img]http://2.bp.blogspot.com/-PBZVKEIWfkc/ULXU0VzWNcI/AAAAAAAAAB0/ODfNUfslpWk/s1600/SCN_0016.jpg[/img]
Authentic Full Rush Signature: (RARE)
[img]http://1.bp.blogspot.com/-Lv_6Hz_CV7I/T47VKTO0leI/AAAAAAAAA30/Dr0ubOD_kYI/s1600/Screen+Shot+2012-04-18+at+7.52.10+AM.png[/img]
Authentic Complete Signature + Personalization and Rushed IP signature:
[img]http://www.mrwillwong.com/wp-content/uploads/2012/09/P1011448.jpg[/img]
Her new Current Authentic Full Signature: (Has a bar under it and loopier L)
[img]https://pbs.twimg.com/media/BoNFCesIMAAq-ED.jpg[/img]
Super rushed authentic signature:
[img]https://scontent-b.xx.fbcdn.net/hphotos-frc3/t1.0-9/574521_10151984828244383_1570008900_n.jpg[/img]
Neat Rushed Signature:
[img]http://4.bp.blogspot.com/-EH6HQKDpQW8/T47TWtfTu9I/AAAAAAAAA3c/UUQn0qDYeY0/s1600/Screen+Shot+2012-04-18+at+7.42.09+AM.png[/img]