Aberdeen's shares fell 2.3p or 4.6% to 461.4p yesterday but much of the fall came before the sale of 1.8 million shares was disclosed as the stock went ex-dividend. The sale of the shares from annual bonus schemes dating back to 2007 leaves Mr Gilbert a stake worth £56,000. But he has conditional and unconditional rights to shares with a paper value of £26m.
Aberdeen, which last month secured a deal to buy Scottish Widows Investment Partnership, said Mr Gilbert has no plans to leave.
Chief investment officer Anne Richards and Asian chief Hugh Young also sold shares.The sales were down to a desire to diversify their portfolios, a spokesman said.