The nation's largest specialty apparel retailer Gap Inc said in a statement on Friday that Canadian firm TRC Capital Corp has begun an unsolicited "mini-tender" offer to buy as many as 20 million Gap shares.

San Francisco-based Gap said it does not recommend or endorse TRC's offer, which represents a stake of around 2.3 per cent.

By seeking less than 5 per cent of a company's stock, tender offers avoid many disclosure and procedural requirements of federal regulators.

They are often used to catch investors off guard, many of whom end up selling their securities at below-market prices. The offer price from TRC Capital is $12 a share, 5 per cent below the $12.60 New York Stock Exchange closing price on Tuesday, the day before TRC began its offer.