Old Second Bancorp (OSBC) shares tumbled 5.05% in the pre-market session on Friday, following the release of the company's mixed fourth-quarter earnings results on Thursday evening.

The regional bank holding company reported a decline in net income for the quarter, citing higher provision for credit losses and non-interest expense. While net interest income improved year-over-year, it fell short of analysts' expectations.

Investors appear to be concerned about the company's profitability and asset quality metrics, as reflected in the pre-market sell-off. The stock's reaction underscores the importance of meeting or exceeding earnings expectations for financial institutions in the current economic climate.