Shares in home credit firm Internaional Personal Finance (IPF) plummeted on Friday morning after the news of a fine in Poland.As markets reopened following the Christmas break, investors were reacting to a statement released late on Tuesday detailing a £2.4m fine relating to "a collective infringement of consumer interests" by its business in Poland. The company said that after taking legal advice, "we believe that we are correctly calculating the total cost of credit and APR and are planning to appeal the decision".However, it will be a "number of months" before a final ruling is received. "At this stage, it is not possible to estimate the impact, if any, a final negative ruling might have on IPF's Polish business. We will continue to review the position and a further announcement will be made as appropriate."IPF released another statement on Friday saying that it would host a conference call to provide further context on the fine and its response.Poland accounts for around 45% of IPF's profits, according to analysts at Numis Securities, who have placed their rating for the stock under review.The share price was down 18.7% at 439p by 10:19, having dropped as low as 390p early on.BC