1965 Topps Bob Schmidt #20. Unlike most Topps cards with these cut/splice/whatever lines, this one has it on front and back.

1948 Leaf #78 Clarence Self, with sheet marks in the top left is recurring.

1964 Topps #170 Don Rodgers. The blue dot in bottom border on off center cards is recurring.

Exhibits Charley Conerly comes with or without the big slash between his helmet and his hand. Both are common

Somewhere around 50% of 1956 Topps #96 Buddy Young cards have a yellow bottom right corner, like this one.

I also found and bought this copy, with yellow splotching on the bottom left. Not sure if a recurring defect to note or just a random one off. Pretty much any old Topps card can be found with yellow-ink splotching if one looks at enough copies.

Young was only 5'4 and is one of the shortest pro football players. He set some track records before his NFL career, and was a college ball star even as a Freshman. He was the first Colt to have his number retired. With the small set sizes in the 50's, most 'common cards' were actually really good players.

Here is one of mine from the same year. AKA Hunter

1962 Topps Missing Yellow ink?
 

I've seen a few of these 'Blue Box/White Letters' Ernie Davis RCs. A couple are on eBay right now. Looks like a print defect - missing yellow ink? I tried looking for other Green Box/Yellow letter players but couldn't find any examples.

Looks like extended sunlight exposure to me.

That was my first thought. I have seen probably 4-5 of these. There is a PSA 8 on eBay right now. Just odd to see that many with the same 'exposure' or same level of damage. I'll hope to find another player someday....

1962t
 

Looking at COMC - found these blue/green examples. Partials only, however.
One is a 50/50 that looks like damage (sun or water?). The other is just the upper right corner of the green box. Weird?

1974 Topps #451 Ken Stabler comes with sheet text on the right side.

1975 Topps #120 Len Dawson. The red/yellow line at top is pretty common. The red spot above the top black border is recurring independent of the red/yellow line on cards off center to the top as well.

Recurring but pretty tough; 2 on COMC, 1 on eBay, 0 in my hoard of 71's. 1971 Topps #172 Garry Garrison with white streak next to his hair.

1972 Topps #311 Doug Cunningham. Note that his neck is entirely printed in red. I think this error may have never been corrected, I can't seem to find a copy without the 'bloody neck'. Oops!

1977 Topps Football # 447
 

Is this a legit variation ? # 447 from the 1977 Topps FB Set ( missing black lines in bottom corner ) ?

That's a new one on me, but it is very common, it looks like it is available in slighty less numbers than the correct version. I figured it was probably at the bottom of a sheet and it is, Mean Joe Greene was beside him on the sheet and also has the recurring partially missing border line but it is much less drastic than Fitzgerald.

Not opening the 1990 Pro Set door, but 1989 wasn't that bad and its the 'best card'. I've seen this recurring pattern of numerous red splotches next to Barry Sanders' name a couple times now.

1948 Leaf #30 Paul Governali. He's usually listed as having a dark brown or tan helmet, but there's also a blue version that isn't that hard.

Here is a Baugh that I had not seen before.

https://photos.imageevent.com/mhgt/h...ey%20front.jpg

This is an awesome looking card

I think so too.