Wow, thanks for helpful info, copper. Rep. added.
The key difference between your situation and mindeis that this corporation actually uses a completely different, 3-letter abbreviation as its nickname. I Googled around a bit and found a couple of press reports that referred to this corp. by the 4-letter name I registered, plus observed that acronym also happens to be the group's stock ticker. I figured that, with 10 billion in the coffers and me planning on offering them name for five figures (0.0001% of their capital) on the basis that it may pose some ancillary benefits to them, I didn't think they'd have the will or basis to invoke the UDRP on it.
Thanks for sharing your experience, though. I'll research the topic further before taking any action. If I did sell them the name for $1500 that would still turn me a pretty nice profit margin (plus a good lesson learned) regardless.