FORTUNE — Three tweets so far today from Carl Icahn about Apple (AAPL):
- 10:50 am: Since tweeting about our large position in $AAPL on Aug 13, when the stock was 468 per share, we’ve kept buying shares of this ‘no brainer.’
- 10:50 am: Having purchased $500 million more $AAPL shares in the last two weeks, our investment has crossed the $3 billion mark yesterday.
- 10:51 am: We feel $APPL board is doing great disservice to shareholders by not having markedly increased its buyback. In-depth letter to follow soon.
See also: Apple’s Tim Cook to billionaire Carl Icahn: Step aside