Looks like it is owned by "Mellow Johnnys LLC" and was assessed a taxable value of $1.34M in 2012. It also has a legal description of "PERSONAL PROPERTY COMMERCIAL MELLOW JOHNNY'S BIKE SHOP" which makes me think that he owns it outright.
He also seems to have another property, owned by...
I heard once that most of MJ's revenue is from merchandise sales like shirts, hats, jerseys, kits, etc... Sure they sell bikes too, but I'll bet that the they make 50% less next year. He'd probably be smart to sell it off asap.