Planet13 - 4:58 pm on Jul 4, 2013 (gmt 0)
If they are / were spammy sites, might as well disavow them.
You could use the domain: operator to do so, since it sounds like they were pretty bad domains.
Also, there seems to be lots of sites that "resurrect" dead sites (I guess by mining the wayback machine) to get easy content. So I wouldn't be too surprised if those links start reappearing on various new domains.