It is also an exception in having just one share class; the Thomsons own almost 73 percent of the shares.
However, shareholders may allow different priority ranking among themselves by the use of share classes and options.
The company has had the two share classes since going public in 1969.
Performance varies among share classes because of the fee structures.
With more than 7,000 mutual funds and share classes, there may be better deals available elsewhere.
Load funds are sold in different share classes, which each have a unique fee structure.
Conversion to the new share class should not create a tax liability for most investors, the company said.
"We are certainly looking at the concept of a share class for retirement."
The investor would have accumulated $1.76 million had the share class existed for all 10 years.
Traded public companies are required to provide names and addresses for those shareholders holding at least 5% or more of any share class.