The Ontario Securities Commission has closed its investigation into three former Nortel Networks executives who were acquitted of fraud last year.

The regulator says it's no longer in the public's interest for it to pursue the allegations against ex-CEO Frank Dunn, ex-CFO Douglas Beatty and ex-controller Michael Gollogly. The OSC allegations were originally filed in March 2007.

An Ontario judge found Dunn, Beatty and Gollogly not guilty of fraud last year.

The three were fired in 2004 and accused of being involved in a book-cooking scheme to trigger $12.8 million in bonuses and stock payments to themselves.

At its height in 1999 to 2000, Nortel was worth nearly $300 billion, employed more than 90,000 people globally and was regarded as one Canada's most valuable companies.

In 2009, the company filed for bankruptcy in North America and Europe, shedding thousands of jobs.