I started a thread to get some clearance about all the John/Jack (A./Joseph) Gallagher (Jr.) out there lately. This thread brought some results, but did not solve the main problem: Who is who?

Therefore I have to rely mostly on IMDB to split this monster thread to single common name finding threads...

Here is the thread for:

(C) John Joseph Gallagher (????): Actor - aka. John Joseph Gallager, John Gallager
Known for: Meet the Parents, Extremely Loud and Incredibly Close, The Darjeeling Limited, Repo! The Genetic Opera
Documentation: IMDB as John Joseph Gallagher

The credits out of CLT:

John Gallagher:
• Curb Your Enthusiasm: The Complete Eighth Season - (C) John Joseph Gallagher
• Falling for Grace - (C) John Joseph Gallagher
• Law & Order: The Twelfth Year: 2001-2002 Season - (C) John Joseph Gallagher (person confirmed by Scooter1836) - credit confirmed by Scooter1836
• Repo!: The Genetic Opera - (C) John Joseph Gallagher - credit confirmed by samuelrichardson

John Joseph Gallagher:
• Blood Ties - (C) John Joseph Gallagher - credit confirmed by SwissFilm
• Boardwalk Empire: The Complete First Season - (C) John Joseph Gallagher - credit confirmed by SwissFilm
• Chappelle"s Show: The Complete Series - (C) John Joseph Gallagher
• The Darjeeling Limited - (C) John Joseph Gallagher - credit confirmed by AiAustria
• Extremely Loud & Incredibly Close - (C) John Joseph Gallagher - credit confirmed by ateo357
• The Job: The Complete Series - (C) John Joseph Gallagher
• John Adams - (C) John Joseph Gallagher - credit confirmed by ateo357
• Law & Order: Criminal Intent - The First Year - (C) John Joseph Gallagher
• Law & Order: Criminal Intent: Seizoen 9 - (C) John Joseph Gallagher
• Law & Order: Criminal Intent: The Fifth Year - (C) John Joseph Gallagher
• Law & Order: Criminal Intent: The Ninth Year "10 Season - (C) John Joseph Gallagher
• Law & Order: The Eleventh Year: 2000-2001 Season: Disc Five - (C) John Joseph Gallagher - credit confirmed by Scooter1836
• Law & Order: The Sixteenth Year: 2005-2006 Season - (C) John Joseph Gallagher - credit confirmed by Scooter1836
• Law & Order: The Tenth Year: 1999-2000 Season - (C) John Joseph Gallagher - credit confirmed by Scooter1836
• Law & Order: The Third Year - (C) John Joseph Gallagher - credit confirmed by Scooter1836
• Meet the Parents - (C) John Joseph Gallagher - credit confirmed by AiAustria

Since the currently confirmed credits for John Joseph Gallagher cannot be reached by the unconfirmed John Gallagher credits the common name is John Joseph Gallagher.