Okla. Stat. tit. 68, § 68-804.1: Estate tax lien

For deaths occurring on or after January 1, 2010, no lien

related to estate tax shall attach to any property passing through

the estate of a decedent, by joint tenancy, or otherwise. No order

exempting estate tax liability shall be necessary to authorize the

release of such property or for the title of real property to be

marketable. This shall not be construed as relieving an estate from

lien obligations in effect for deaths occurring before January 1,

2010; provided, that for deaths occurring before January 1, 2010,

any lien related to estate tax shall be extinguished subsequent to

the lapse of ten (10) years after the date of death of a decedent

and no order exempting estate tax liability shall be necessary to

authorize release of such property or for the title of real property

to be marketable.