Should Badfinger Sue XTC?

The 3rd "SHOULD" post.  The 3rd "You stole my 3-4-5-8" post.Two of my last posts have featured pairs of songs that feature the same four (4) notes -  3-4-5-8  -prominently in their choruses/hooks.  The songs from the February 27, 2014 post:

XTC's Then She Appeared (1992)Toby Keith - Red Solo Cup (2011)

The songs from the post before that (February 24, 2014):

Toby Keith - Red Solo Cup (2011)Sebastian Mikael - Last Night ft. Wale (2013)

I raised the possibilities and reasons why these songs could be in litigation. I did NOT advocate that a lawsuit should happen and I did NOT take a side - my purpose was to be illustrative and solicit responses.  I heard "Last Night" by Sebastian Mikael for the first time as I was driving home from the airport in Nashville Sunday night (February 23, 2014) and couldn't help but notice the 3-4-5-8's jumping out of the car radio.  That led to an investigation of the 3-4-5-8 melody as well as the music of Sebastian Mikael, Toby Keith, XTC and now Badfinger._______________________________________________________________________Today I ask a related question and what would be a precedent to the XTC v. Toby Keith case which was a precedent for the Toby Keith v. Sebastian Mikael possibility  - namely, should Badfinger sue XTC for stealing "Badfinger's" 3-4-5-8?

Badfinger's Come And Get It (1970)XTC's Then She Appeared (1992)

The 3-4-5-8 occurs frequently and prominently in Badfinger's Come And Get It although slightly modified with a repeated "5" and "8"  -   3-4-5-5-8-8-8.  (As the song progresses, the  3-4-5-8 that usually features the lyrics "if you want it here it is" and "if you want it anytime" changes from 3-4-5-8 to 8-6-5-5 and other non-3-4-5-8 melodies.)Badfinger's Come And Get It (1970, U.S. release)

0.05  if you want it here it is0.15  if you want it any time0.38  if you want it here it is0.51  if you want it here it is1.02  if you want it any time

XTC's  Then She Appeared (1992) is a song written and recorded almost twenty (20) years before Toby Keith's Red Solo Cup (2011) but more than twenty (20) AFTER Badfinger's Come And Get It (1970).  It also prominently features the 3-4-5-8 melody.  The 3-4-5-8 is the opening vocal and the hook throughout the entire song.The thirteen (13) examples of 3-4-5-8 in Then She Appeared, complete with associated lyrics, are heard here:XTC - Then She Appeared  (1992)

0.22  then she appeared0.31  then she appeared0.50  cherubim cheered0.59  then she appeared1.08  then she appeared1.26  know it sounds weird2.02  then she appeared2.11  then she appeared2.30  all Edward leared3.06  then she appeared3.15  then she appeared3.24  then she appeared3.33  then she appeared

_______________________________________________________________________Are four (4) prominent and clearly-heard notes in common between songs reason enough to instigate a copyright infringement lawsuit?  As mentioned before, one answer could be found in comparing this hypothetical (or not) Badfinger v. XTC music copyright infringement case to the actual Marvin Gaye v. Robin Thicke copyright infringement case in which NO notes were in common between the songs.If one can sue when the similarity is only STYLE and NOT melody, surely one is even more likely to sue when the similarity is MELODY and not STYLE.(Do any/all the tags in this post have any bearing on the merit of this potential copyright infringement lawsuit?)As always, I welcome your comments.