12 CFR §1010.9

1. (a)The sale of lots in a subdivision is exempt from the registration requirements of the Act if, since April 28, 1969, each lot in the subdivision has contained at least twenty acres. In determining eligibility for the exemption, easements for ingress and egress or public utilities are considered part of the total acreage of the lot if the purchaser retains ownership of the property affected by the easement.
2. (b)The sale must also comply with the anti-fraud provisions of § 1010.4(b) and (c) of this part.