In 2007, 14 Dutch men having sex with men (MSM) filed a criminal case against three other men, accusing them of administering sedative drugs, sexual abuse, and deliberate subcutaneous injections with HIV-1-infected blood. Medical files showed that 9 of 17 men presented with an acute HIV-1 infection syndrome during 2006-2007. Two men were not infected with HIV. Analysis of viral strains in the 12 MSM and the three alleged donors showed that one donor and six recipients were double infected with two distinct HIV-1 subtype B strains, while another five recipients and one donor were single infected with either strain. Two men were infected with unrelated strains. The finding of multiple double infections with very similar HIV-1 strains is without precedent.