Plato Investments, which has shorted Bank of Queensland for more than 18 months, is confident the regional lender will continue to underperform the market and its peers despite a late-year sharemarket rally that prompted short-sellers to close off their positions.

The company is up 7.9 per cent to $6.14 in the last month and, while it is still below the $6.90 it started last year at, short interest in BoQ has fallen over the same time. In November, 9.9 per cent of its shares were shorted, whereas it is now 6.2 per cent, Australian Securities and Investment Commission data shows.