BlackRock to Buy Custom Indexing Business Aperio for $1 Billion

BlackRock Inc. is betting on the future of personalized index investing.

The world’s biggest asset manager agreed to buy Aperio, a creator of tailored index strategies, from private equity firm Golden Gate Capital and Aperio employees for $1.05 billion in cash, according to a statement Monday. Sausalito, California-based Aperio oversaw about $36 billion in assets as of Sept. 30 for ultra-wealthy clients and institutions.

The move advances BlackRock further into an approach that’s gaining popularity among the rich, who can tweak broad indexes of companies for tax reasons and personal preferences. BlackRock, a longstanding champion of cheap, passive investing, ...