Being vetted for VP apparently jogged his memory in June...
http://www.usatoday.com/news/politics/story/2012-08-15/paul-ryan-finances-reports/57078160/1?csp=Dailybriefing While being vetted by Mitt Romney's campaign, GOP vice presidential hopeful Rep. Paul Ryan amended two years of his financial disclosure statements to add an income-producing trust worth between $1 million and $5 million that he had previously neglected to report.
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The trust was created in 2010 following the death of Janna Ryan's mother, Prudence Little, a prominent Oklahoma attorney. Janna Ryan's remaining interest in the trust is estimated between $1,000,001 and $5 million, according to the amended filings.
Ryan's amended reports were hand delivered to the House Clerk with letters characterizing the belated disclosures as an "inadvertent omission."
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Craig Holman, a government affairs lobbyist for Public Citizen, a consumer advocacy group, said "the amount and timing of this new disclosure suggests that Ryan had not sought to be fully transparent about his income and investments until he felt compelled to do so."