In Matter of Christo's, Inc., a restaurant sought to sponsor a cook for his permanent residence. The beneficiary was also the beneficiary of a marriage-based petition. However, he claimed that the marriage certificate submitted with that petition was false, and that he had never married or met the other party named in the certificate. United States Citizenship and Immigration Services (USCIS) revoked the previously approved employment-based petition, finding that the beneficiary had engaged in a fraudulent marriage for the purpose of obtaining an immigration benefit, and thus, was barred from being the beneficiary of any immigrant petition, such as the one submitted by the sponsoring employer. The beneficiary's adjustment of status application was also denied. Initially, the AAO agreed that the marriage fraud barred applied.
Upon additional review, the AAO determined that the marriage fraud bar was not implicated. "An alien who submits false documents representing a nonexistent or fictitious marriage, but who never either entered into or attempted or conspired to enter into a marriage, may intend to evade the immigration laws, but is not, by such act alone, considered to have 'entered into' or attempted or conspired to enter into' a [fraudulent] marriage." Such conduct, may, however, render an individual inadmissible for making a material misrepresentation for the purpose of obtaining an immigration benefit.
The full text of Matter of Cristo's, Inc. can be found here: http://www.justice.gov/eoir/vll/intdec/vol26/3831.pdf