One of the US’s most prominent brokerages has quietly become a major shareholder in two of the big three global music recording companies over the past few years. Boston-headquartered Fidelity Investments, the second-largest brokerage in the US, has snapped up around $1.125 billion worth of shares inUniversal Music Group, the world’s largest music rights holder, and about $450 million–worth of shares in Warner Music Group, the third-largest rights holder.