RIM’s short interest has hit a record high, increasing to 4.2% of shares outstanding on August 24, finds research firm Markit.

This is a sign investors are anticipating disappointing earnings as they continue to wait for a new lineup of BlackBerry smartphones, says Hugo Miller of Bloomberg Businessweek.

Read: RIM chair defends leadership

Investors taking short positions bet against a stock by borrowing shares and selling them. They profit by repaying the borrowed shares at a lower price.

Read: Nothing wrong with RIM

RIM shares have declined 54% this year. Today, at 1:30pm, RIM fell 1.21% to US$6.61.

Read more about RIM’s stock

Read: Former RIM employee conducted insider trading: OSC