K Street powerhouses Mercury and the Podesta Group recently hired outside lawyers after the Associated Press reported that their work for a European think tank was secretly overseen by [Donald Trump campaign chairman Paul] Manafort and one of his associates working for a pro-Russian political party in Ukraine. Manafort and his company never registered their activities under FARA.
The IG report noted ambiguity about whether exemptions apply to representing foreign entities like college campus groups and think thanks that receive government funding but claim to act independently.
FARA registrations peaked in 1987 and fell sharply since the 1990s, probably because people started registering under the 1995 domestic lobbying law instead, which requires less detailed disclosures.
The "think tank" mentioned above is European Centre for a Modern Ukraine (ECFMU), based in Brussels, Belgium. Here is more about that organization, which was founded in 2012.