Michaels Stores

(MIK) - Get Report

received a letter from the

Securities and Exchange Commission

requesting that the company keep all documents relating to its stock-options grants dating back to 1990.

In a brief SEC filing Thursday, the arts-and-crafts retailer said the agency also plans to request production of those documents in the future.

Michaels has launched an internal review into its options-grants practices from 1990 to 2001. The company said

in its quarterly report Tuesday that it identified certain options grants in that period that may have used an exercise date that differed from the measurement date as required by its accounting policy.

The retailer said the discrepancy could lead to additional expenses of up to $60 million, but also said any restatements wouldn't affect shareholders' equity.

Michaels' review comes against the backdrop of a widespread investigation into stock-options practices at more than 30 companies. The issue stems from the "backdating" of stock options, or granting options an exercise date at a time when stock prices were lower to create greater profits for the recipient.