By Christiana Stewart-Lockhart Over the last 30 years the Enterprise Investment Scheme (EIS) has provided £32bn of private investment into 56,000 businesses, says Christiana Stewart-Lockhart This year marks 30 years of the Enterprise Investment Scheme (EIS), the tax relief that encourages investors to back risky early-stage companies that might – just might – go on to change the world. It is not often a piece of tax legislation deserves a birthday celebration, but the EIS is an exception. Along with its younger sister, the Seed Enterprise Investment Scheme (SEIS), the EIS has provided £32bn of…