First, it's worth noting that there is no "the copyright." Each issue has an independent copyright, so relying exclusively on the "first renewal" list overlooks which issues may or may not have been renewed.
In any case, to follow up on Yoc's comments, we've been trying to work through the details on our end, but it's been slow-going for a number of reasons. There are a few books here and there that got "grandfathered in," from site to site, having been assumed public domain for literally decades, that haven't been specifically researched by us.
On top of that, there's circumstantial evidence that many renewals were filed by people who didn't own the copyright. Those transfer records aren't online, though, and so will presumably require my spending a few days at the Library of Congress to track down. But it's worth pointing out that "rights transfers" very rarely include copyrights, so many renewals by someone other than the original holding company (as opposed to an individual who died and the work was renewed by an heir) can be outright bogus.
(Legally speaking, because the books come from contributors, we're a "safe haven" under the DMCA. As long as there's confusion about the status--so don't try this with the Avengers movie--and we remove books when asked by the copyright holder, we're in good shape as an organization. In the case of Standard/Nedor, nobody has been sent a Cease and Desist or DMCA notice, which argues for the abandonment theory at a minimum.)
The upshot, as always, is that we're comfortable with what we have posted (though I'd always like to be more comfortable) at this time, but anybody using the books for another purpose would be well-advised to do their own research and make their own decisions, possibly including a visit to an Intellectual Property lawyer, if you're planning on involving money.
