Shares in Octagon surged almost 50% early on Friday, after the investment company said it has agreed to acquire the remainder of financial service business provider Global Investment Strategy UK (GIS).In April, the company, which did not provide any financial details of the acquisition, had acquired a 9.97% in GIS and said the new deal was in line with its investing policy.However, the deal will result in a drastic change in the business and will constitute a reverse takeover under AIM rules, which means the acquisition remains subject to shareholders approval, Octagon said.Should the transaction receive the green light, the new company will become a financial services group, focused on providing safe custody services and settlement.Meanwhile, the London-listed group has raised £1.7m by means of subscription, which will be used to fund part of the deal and for general working capital requirements.Octagon shares were up 72.97% to 0.320p at 08:35 on Friday.