I'm trying to analyse 13F filings and those provide CUSIPs and names. I hoped the names would be sufficient to find the relevant Edgar filings but the names are often imprecise (e.g., "ABBOTT LABS" instead of "ABBOTT LABORATORIES" so Edgar search fails).
If I had a way to reliably map CUSIPs to CIKs that would solve my problem - but "official" way of https://www.sec.gov/edgar/NYU/cik.coleft.c is a mapping from names to CIKs and again the names in 13F don't match the names in that file.
So my question is - what's the best free way to get from CUSIPs to CIKs? Or alternatively from CUSIPs to the same names as Edgar uses?