ok, I think I found out who owns the Mt.Pass plant. It's Molycorp.
per company news in Mar.31st:
"The confirmed Plan allows Molycorp’s downstream business units, Chemicals & Oxides, Magnequench, and Rare Metals to reorganize under new ownership with a significantly stronger balance sheet. The Plan features a settlement agreement between an affiliate of funds managed by Oaktree Capital Management L.P. (“Oaktree”), a secured creditor, and unsecured creditors, pursuant to which Oaktree will receive 92.5% of the equity and the unsecured creditors will receive 7.5% of the equity in the reorganized company. A settlement also was reached on the purchase through a credit bid by the ad hoc group of the Company’s 10% secured noteholders of the mineral rights and certain intellectual property of Molycorp Minerals (the “Sale”). The ad hoc group of 10% secured noteholders was the last major secured creditor group with which the Company had not reached a settlement in a mediation process that spanned several months.
Molycorp’s Mountain Pass mine was excluded from the Plan, and the equipment and surface property rights at the mine were excluded from the Sale."
