Singular domain; now the plural has a website; what do I do?

[dbdomains]

I purchased a nice brandable domain in 2011 with the intent to develop. At the time the plural of the term had only a parking page which said that the domain was for sale. It would be sold a little later by Marchex for a significant sum. The person who bought the plural put up a website in mid-2012 - "scooped" me, so to speak.

It is a valuable domain so I don't want to just walk away. But I am concerned that if I build a site that I will be claimed to be infringing. The plural owner has no registered trademark, but does appear to be doing business. Because I bought the domain to build my own site before he had a site up, I feel pretty safe owning the domain. But it doesn't do me a lot of good unless it is built on or I can sell it. I am also concerned that if I approach the plural owner about buying my singular version domain he will claim "bad faith" under UDRP.

What do you think I should do?

 

[dbdomains]

No ideas or suggestions from anyone?

 

[Cartoonz]

I purchased a nice brandable domain in 2011...
At the time the plural of the term had only a parking page which said that the domain was for sale. It would be sold a little later by Marchex for a significant sum.
The person who bought the plural put up a website in mid-2012...

..The plural owner has no registered trademark.

Seems pretty obvious to me.
Look, anyone can "claim" anything. Sure they "could" file a UDRP, but they would not likely actually win.

 

[dbdomains]

Thanks Cartoonz. That's the way I am leaning as well.