Bell Labs continued doing foundational research unfettered by marketability for a long time after the conventional story has them buried and gone. (To pick a personal favourite, B. F. Logan's work on Click Modulation is a bizarro-world stumble through arcane mathematics that pops out somewhere unexpected and valuable in the field of signal processing.)

Unfortunately, a lot of this research was buried in microfiche in university basements as Bell Labs' legacy was traded from company to company without a viable distribution mechanism. As a result, although this work is now all available on-line (sadly not in open-access form), there are still more forgotten gems in there than many researchers realize.